hso.c

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/******************************************************************************
 *
 * Driver for Option High Speed Mobile Devices.
 *
 *  Copyright (C) 2008 Option International
 *                     Filip Aben <[email protected]>
 *                     Denis Joseph Barrow <[email protected]>
 *                     Jan Dumon <[email protected]>
 *  Copyright (C) 2007 Andrew Bird (Sphere Systems Ltd)
 *              <[email protected]>
 *  Copyright (C) 2008 Greg Kroah-Hartman <[email protected]>
 *  Copyright (C) 2008 Novell, Inc.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 *  USA
 *
 *
 *****************************************************************************/

/******************************************************************************
 *
 * Description of the device:
 *
 * Interface 0: Contains the IP network interface on the bulk end points.
 *      The multiplexed serial ports are using the interrupt and
 *      control endpoints.
 *      Interrupt contains a bitmap telling which multiplexed
 *      serialport needs servicing.
 *
 * Interface 1: Diagnostics port, uses bulk only, do not submit urbs until the
 *      port is opened, as this have a huge impact on the network port
 *      throughput.
 *
 * Interface 2: Standard modem interface - circuit switched interface, this
 *      can be used to make a standard ppp connection however it
 *              should not be used in conjunction with the IP network interface
 *              enabled for USB performance reasons i.e. if using this set
 *              ideally disable_net=1.
 *
 *****************************************************************************/

#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/module.h>
#include <linux/ethtool.h>
#include <linux/usb.h>
#include <linux/timer.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/kmod.h>
#include <linux/rfkill.h>
#include <linux/ip.h>
#include <linux/uaccess.h>
#include <linux/usb/cdc.h>
#include <net/arp.h>
#include <asm/byteorder.h>
#include <linux/serial_core.h>
#include <linux/serial.h>


#define MOD_AUTHOR          "Option Wireless"
#define MOD_DESCRIPTION         "USB High Speed Option driver"
#define MOD_LICENSE         "GPL"

#define HSO_MAX_NET_DEVICES     10
#define HSO__MAX_MTU            2048
#define DEFAULT_MTU         1500
#define DEFAULT_MRU         1500

#define CTRL_URB_RX_SIZE        1024
#define CTRL_URB_TX_SIZE        64

#define BULK_URB_RX_SIZE        4096
#define BULK_URB_TX_SIZE        8192

#define MUX_BULK_RX_BUF_SIZE        HSO__MAX_MTU
#define MUX_BULK_TX_BUF_SIZE        HSO__MAX_MTU
#define MUX_BULK_RX_BUF_COUNT       4
#define USB_TYPE_OPTION_VENDOR      0x20

/* These definitions are used with the struct hso_net flags element */
/* - use *_bit operations on it. (bit indices not values.) */
#define HSO_NET_RUNNING         0

#define HSO_NET_TX_TIMEOUT      (HZ*10)

#define HSO_SERIAL_MAGIC        0x48534f31

/* Number of ttys to handle */
#define HSO_SERIAL_TTY_MINORS       256

#define MAX_RX_URBS         2

/*****************************************************************************/
/* Debugging functions                                                       */
/*****************************************************************************/
#define D__(lvl_, fmt, arg...)              \
    do {                        \
        printk(lvl_ "[%d:%s]: " fmt "\n",   \
               __LINE__, __func__, ## arg); \
    } while (0)

#define D_(lvl, args...)                \
    do {                        \
        if (lvl & debug)            \
            D__(KERN_INFO, args);       \
    } while (0)

#define D1(args...) D_(0x01, ##args)
#define D2(args...) D_(0x02, ##args)
#define D3(args...) D_(0x04, ##args)
#define D4(args...) D_(0x08, ##args)
#define D5(args...) D_(0x10, ##args)

/*****************************************************************************/
/* Enumerators                                                               */
/*****************************************************************************/
enum pkt_parse_state {
    WAIT_IP,
    WAIT_DATA,
    WAIT_SYNC
};

/*****************************************************************************/
/* Structs                                                                   */
/*****************************************************************************/

struct hso_shared_int {
    struct usb_endpoint_descriptor *intr_endp;
    void *shared_intr_buf;
    struct urb *shared_intr_urb;
    struct usb_device *usb;
    int use_count;
    int ref_count;
    struct mutex shared_int_lock;
};

struct hso_net {
    struct hso_device *parent;
    struct net_device *net;
    struct rfkill *rfkill;

    struct usb_endpoint_descriptor *in_endp;
    struct usb_endpoint_descriptor *out_endp;

    struct urb *mux_bulk_rx_urb_pool[MUX_BULK_RX_BUF_COUNT];
    struct urb *mux_bulk_tx_urb;
    void *mux_bulk_rx_buf_pool[MUX_BULK_RX_BUF_COUNT];
    void *mux_bulk_tx_buf;

    struct sk_buff *skb_rx_buf;
    struct sk_buff *skb_tx_buf;

    enum pkt_parse_state rx_parse_state;
    spinlock_t net_lock;

    unsigned short rx_buf_size;
    unsigned short rx_buf_missing;
    struct iphdr rx_ip_hdr;

    unsigned long flags;
};

enum rx_ctrl_state{
    RX_IDLE,
    RX_SENT,
    RX_PENDING
};

#define BM_REQUEST_TYPE (0xa1)
#define B_NOTIFICATION  (0x20)
#define W_VALUE         (0x0)
#define W_INDEX         (0x2)
#define W_LENGTH        (0x2)

#define B_OVERRUN       (0x1<<6)
#define B_PARITY        (0x1<<5)
#define B_FRAMING       (0x1<<4)
#define B_RING_SIGNAL   (0x1<<3)
#define B_BREAK         (0x1<<2)
#define B_TX_CARRIER    (0x1<<1)
#define B_RX_CARRIER    (0x1<<0)

struct hso_serial_state_notification {
    u8 bmRequestType;
    u8 bNotification;
    u16 wValue;
    u16 wIndex;
    u16 wLength;
    u16 UART_state_bitmap;
} __packed;

struct hso_tiocmget {
    struct mutex mutex;
    wait_queue_head_t waitq;
    int    intr_completed;
    struct usb_endpoint_descriptor *endp;
    struct urb *urb;
    struct hso_serial_state_notification serial_state_notification;
    u16    prev_UART_state_bitmap;
    struct uart_icount icount;
};


struct hso_serial {
    struct hso_device *parent;
    int magic;
    u8 minor;

    struct hso_shared_int *shared_int;

    /* rx/tx urb could be either a bulk urb or a control urb depending
       on which serial port it is used on. */
    struct urb *rx_urb[MAX_RX_URBS];
    u8 num_rx_urbs;
    u8 *rx_data[MAX_RX_URBS];
    u16 rx_data_length; /* should contain allocated length */

    struct urb *tx_urb;
    u8 *tx_data;
    u8 *tx_buffer;
    u16 tx_data_length; /* should contain allocated length */
    u16 tx_data_count;
    u16 tx_buffer_count;
    struct usb_ctrlrequest ctrl_req_tx;
    struct usb_ctrlrequest ctrl_req_rx;

    struct usb_endpoint_descriptor *in_endp;
    struct usb_endpoint_descriptor *out_endp;

    enum rx_ctrl_state rx_state;
    u8 rts_state;
    u8 dtr_state;
    unsigned tx_urb_used:1;

    struct tty_port port;
    /* from usb_serial_port */
    spinlock_t serial_lock;

    int (*write_data) (struct hso_serial *serial);
    struct hso_tiocmget  *tiocmget;
    /* Hacks required to get flow control
     * working on the serial receive buffers
     * so as not to drop characters on the floor.
     */
    int  curr_rx_urb_idx;
    u16  curr_rx_urb_offset;
    u8   rx_urb_filled[MAX_RX_URBS];
    struct tasklet_struct unthrottle_tasklet;
    struct work_struct    retry_unthrottle_workqueue;
};

struct hso_device {
    union {
        struct hso_serial *dev_serial;
        struct hso_net *dev_net;
    } port_data;

    u32 port_spec;

    u8 is_active;
    u8 usb_gone;
    struct work_struct async_get_intf;
    struct work_struct async_put_intf;
    struct work_struct reset_device;

    struct usb_device *usb;
    struct usb_interface *interface;

    struct device *dev;
    struct kref ref;
    struct mutex mutex;
};

/* Type of interface */
#define HSO_INTF_MASK       0xFF00
#define HSO_INTF_MUX        0x0100
#define HSO_INTF_BULK       0x0200

/* Type of port */
#define HSO_PORT_MASK       0xFF
#define HSO_PORT_NO_PORT    0x0
#define HSO_PORT_CONTROL    0x1
#define HSO_PORT_APP        0x2
#define HSO_PORT_GPS        0x3
#define HSO_PORT_PCSC       0x4
#define HSO_PORT_APP2       0x5
#define HSO_PORT_GPS_CONTROL    0x6
#define HSO_PORT_MSD        0x7
#define HSO_PORT_VOICE      0x8
#define HSO_PORT_DIAG2      0x9
#define HSO_PORT_DIAG       0x10
#define HSO_PORT_MODEM      0x11
#define HSO_PORT_NETWORK    0x12

/* Additional device info */
#define HSO_INFO_MASK       0xFF000000
#define HSO_INFO_CRC_BUG    0x01000000

/*****************************************************************************/
/* Prototypes                                                                */
/*****************************************************************************/
/* Serial driver functions */
static int hso_serial_tiocmset(struct tty_struct *tty,
                   unsigned int set, unsigned int clear);
static void ctrl_callback(struct urb *urb);
static int put_rxbuf_data(struct urb *urb, struct hso_serial *serial);
static void hso_kick_transmit(struct hso_serial *serial);
/* Helper functions */
static int hso_mux_submit_intr_urb(struct hso_shared_int *mux_int,
                   struct usb_device *usb, gfp_t gfp);
static void handle_usb_error(int status, const char *function,
                 struct hso_device *hso_dev);
static struct usb_endpoint_descriptor *hso_get_ep(struct usb_interface *intf,
                          int type, int dir);
static int hso_get_mux_ports(struct usb_interface *intf, unsigned char *ports);
static void hso_free_interface(struct usb_interface *intf);
static int hso_start_serial_device(struct hso_device *hso_dev, gfp_t flags);
static int hso_stop_serial_device(struct hso_device *hso_dev);
static int hso_start_net_device(struct hso_device *hso_dev);
static void hso_free_shared_int(struct hso_shared_int *shared_int);
static int hso_stop_net_device(struct hso_device *hso_dev);
static void hso_serial_ref_free(struct kref *ref);
static void hso_std_serial_read_bulk_callback(struct urb *urb);
static int hso_mux_serial_read(struct hso_serial *serial);
static void async_get_intf(struct work_struct *data);
static void async_put_intf(struct work_struct *data);
static int hso_put_activity(struct hso_device *hso_dev);
static int hso_get_activity(struct hso_device *hso_dev);
static void tiocmget_intr_callback(struct urb *urb);
static void reset_device(struct work_struct *data);
/*****************************************************************************/
/* Helping functions                                                         */
/*****************************************************************************/

/* #define DEBUG */

static inline struct hso_net *dev2net(struct hso_device *hso_dev)
{
    return hso_dev->port_data.dev_net;
}

static inline struct hso_serial *dev2ser(struct hso_device *hso_dev)
{
    return hso_dev->port_data.dev_serial;
}

/* Debugging functions */
#ifdef DEBUG
static void dbg_dump(int line_count, const char *func_name, unsigned char *buf,
             unsigned int len)
{
    static char name[255];

    sprintf(name, "hso[%d:%s]", line_count, func_name);
    print_hex_dump_bytes(name, DUMP_PREFIX_NONE, buf, len);
}

#define DUMP(buf_, len_)    \
    dbg_dump(__LINE__, __func__, (unsigned char *)buf_, len_)

#define DUMP1(buf_, len_)           \
    do {                    \
        if (0x01 & debug)       \
            DUMP(buf_, len_);   \
    } while (0)
#else
#define DUMP(buf_, len_)
#define DUMP1(buf_, len_)
#endif

/* module parameters */
static int debug;
static int tty_major;
static int disable_net;

/* driver info */
static const char driver_name[] = "hso";
static const char tty_filename[] = "ttyHS";
static const char *version = __FILE__ ": " MOD_AUTHOR;
/* the usb driver itself (registered in hso_init) */
static struct usb_driver hso_driver;
/* serial structures */
static struct tty_driver *tty_drv;
static struct hso_device *serial_table[HSO_SERIAL_TTY_MINORS];
static struct hso_device *network_table[HSO_MAX_NET_DEVICES];
static spinlock_t serial_table_lock;

static const s32 default_port_spec[] = {
    HSO_INTF_MUX | HSO_PORT_NETWORK,
    HSO_INTF_BULK | HSO_PORT_DIAG,
    HSO_INTF_BULK | HSO_PORT_MODEM,
    0
};

static const s32 icon321_port_spec[] = {
    HSO_INTF_MUX | HSO_PORT_NETWORK,
    HSO_INTF_BULK | HSO_PORT_DIAG2,
    HSO_INTF_BULK | HSO_PORT_MODEM,
    HSO_INTF_BULK | HSO_PORT_DIAG,
    0
};

#define default_port_device(vendor, product)    \
    USB_DEVICE(vendor, product),    \
        .driver_info = (kernel_ulong_t)default_port_spec

#define icon321_port_device(vendor, product)    \
    USB_DEVICE(vendor, product),    \
        .driver_info = (kernel_ulong_t)icon321_port_spec

/* list of devices we support */
static const struct usb_device_id hso_ids[] = {
    {default_port_device(0x0af0, 0x6711)},
    {default_port_device(0x0af0, 0x6731)},
    {default_port_device(0x0af0, 0x6751)},
    {default_port_device(0x0af0, 0x6771)},
    {default_port_device(0x0af0, 0x6791)},
    {default_port_device(0x0af0, 0x6811)},
    {default_port_device(0x0af0, 0x6911)},
    {default_port_device(0x0af0, 0x6951)},
    {default_port_device(0x0af0, 0x6971)},
    {default_port_device(0x0af0, 0x7011)},
    {default_port_device(0x0af0, 0x7031)},
    {default_port_device(0x0af0, 0x7051)},
    {default_port_device(0x0af0, 0x7071)},
    {default_port_device(0x0af0, 0x7111)},
    {default_port_device(0x0af0, 0x7211)},
    {default_port_device(0x0af0, 0x7251)},
    {default_port_device(0x0af0, 0x7271)},
    {default_port_device(0x0af0, 0x7311)},
    {default_port_device(0x0af0, 0xc031)},  /* Icon-Edge */
    {icon321_port_device(0x0af0, 0xd013)},  /* Module HSxPA */
    {icon321_port_device(0x0af0, 0xd031)},  /* Icon-321 */
    {icon321_port_device(0x0af0, 0xd033)},  /* Icon-322 */
    {USB_DEVICE(0x0af0, 0x7301)},       /* GE40x */
    {USB_DEVICE(0x0af0, 0x7361)},       /* GE40x */
    {USB_DEVICE(0x0af0, 0x7381)},       /* GE40x */
    {USB_DEVICE(0x0af0, 0x7401)},       /* GI 0401 */
    {USB_DEVICE(0x0af0, 0x7501)},       /* GTM 382 */
    {USB_DEVICE(0x0af0, 0x7601)},       /* GE40x */
    {USB_DEVICE(0x0af0, 0x7701)},
    {USB_DEVICE(0x0af0, 0x7706)},
    {USB_DEVICE(0x0af0, 0x7801)},
    {USB_DEVICE(0x0af0, 0x7901)},
    {USB_DEVICE(0x0af0, 0x7A01)},
    {USB_DEVICE(0x0af0, 0x7A05)},
    {USB_DEVICE(0x0af0, 0x8200)},
    {USB_DEVICE(0x0af0, 0x8201)},
    {USB_DEVICE(0x0af0, 0x8300)},
    {USB_DEVICE(0x0af0, 0x8302)},
    {USB_DEVICE(0x0af0, 0x8304)},
    {USB_DEVICE(0x0af0, 0x8400)},
    {USB_DEVICE(0x0af0, 0x8600)},
    {USB_DEVICE(0x0af0, 0x8800)},
    {USB_DEVICE(0x0af0, 0x8900)},
    {USB_DEVICE(0x0af0, 0x9000)},
    {USB_DEVICE(0x0af0, 0xd035)},
    {USB_DEVICE(0x0af0, 0xd055)},
    {USB_DEVICE(0x0af0, 0xd155)},
    {USB_DEVICE(0x0af0, 0xd255)},
    {USB_DEVICE(0x0af0, 0xd057)},
    {USB_DEVICE(0x0af0, 0xd157)},
    {USB_DEVICE(0x0af0, 0xd257)},
    {USB_DEVICE(0x0af0, 0xd357)},
    {USB_DEVICE(0x0af0, 0xd058)},
    {USB_DEVICE(0x0af0, 0xc100)},
    {}
};
MODULE_DEVICE_TABLE(usb, hso_ids);

/* Sysfs attribute */
static ssize_t hso_sysfs_show_porttype(struct device *dev,
                       struct device_attribute *attr,
                       char *buf)
{
    struct hso_device *hso_dev = dev_get_drvdata(dev);
    char *port_name;

    if (!hso_dev)
        return 0;

    switch (hso_dev->port_spec & HSO_PORT_MASK) {
    case HSO_PORT_CONTROL:
        port_name = "Control";
        break;
    case HSO_PORT_APP:
        port_name = "Application";
        break;
    case HSO_PORT_APP2:
        port_name = "Application2";
        break;
    case HSO_PORT_GPS:
        port_name = "GPS";
        break;
    case HSO_PORT_GPS_CONTROL:
        port_name = "GPS Control";
        break;
    case HSO_PORT_PCSC:
        port_name = "PCSC";
        break;
    case HSO_PORT_DIAG:
        port_name = "Diagnostic";
        break;
    case HSO_PORT_DIAG2:
        port_name = "Diagnostic2";
        break;
    case HSO_PORT_MODEM:
        port_name = "Modem";
        break;
    case HSO_PORT_NETWORK:
        port_name = "Network";
        break;
    default:
        port_name = "Unknown";
        break;
    }

    return sprintf(buf, "%s\n", port_name);
}
static DEVICE_ATTR(hsotype, S_IRUGO, hso_sysfs_show_porttype, NULL);

static int hso_urb_to_index(struct hso_serial *serial, struct urb *urb)
{
    int idx;

    for (idx = 0; idx < serial->num_rx_urbs; idx++)
        if (serial->rx_urb[idx] == urb)
            return idx;
    dev_err(serial->parent->dev, "hso_urb_to_index failed\n");
    return -1;
}

/* converts mux value to a port spec value */
static u32 hso_mux_to_port(int mux)
{
    u32 result;

    switch (mux) {
    case 0x1:
        result = HSO_PORT_CONTROL;
        break;
    case 0x2:
        result = HSO_PORT_APP;
        break;
    case 0x4:
        result = HSO_PORT_PCSC;
        break;
    case 0x8:
        result = HSO_PORT_GPS;
        break;
    case 0x10:
        result = HSO_PORT_APP2;
        break;
    default:
        result = HSO_PORT_NO_PORT;
    }
    return result;
}

/* converts port spec value to a mux value */
static u32 hso_port_to_mux(int port)
{
    u32 result;

    switch (port & HSO_PORT_MASK) {
    case HSO_PORT_CONTROL:
        result = 0x0;
        break;
    case HSO_PORT_APP:
        result = 0x1;
        break;
    case HSO_PORT_PCSC:
        result = 0x2;
        break;
    case HSO_PORT_GPS:
        result = 0x3;
        break;
    case HSO_PORT_APP2:
        result = 0x4;
        break;
    default:
        result = 0x0;
    }
    return result;
}

static struct hso_serial *get_serial_by_shared_int_and_type(
                    struct hso_shared_int *shared_int,
                    int mux)
{
    int i, port;

    port = hso_mux_to_port(mux);

    for (i = 0; i < HSO_SERIAL_TTY_MINORS; i++) {
        if (serial_table[i] &&
            (dev2ser(serial_table[i])->shared_int == shared_int) &&
            ((serial_table[i]->port_spec & HSO_PORT_MASK) == port)) {
            return dev2ser(serial_table[i]);
        }
    }

    return NULL;
}

static struct hso_serial *get_serial_by_index(unsigned index)
{
    struct hso_serial *serial = NULL;
    unsigned long flags;

    spin_lock_irqsave(&serial_table_lock, flags);
    if (serial_table[index])
        serial = dev2ser(serial_table[index]);
    spin_unlock_irqrestore(&serial_table_lock, flags);

    return serial;
}

static int get_free_serial_index(void)
{
    int index;
    unsigned long flags;

    spin_lock_irqsave(&serial_table_lock, flags);
    for (index = 0; index < HSO_SERIAL_TTY_MINORS; index++) {
        if (serial_table[index] == NULL) {
            spin_unlock_irqrestore(&serial_table_lock, flags);
            return index;
        }
    }
    spin_unlock_irqrestore(&serial_table_lock, flags);

    printk(KERN_ERR "%s: no free serial devices in table\n", __func__);
    return -1;
}

static void set_serial_by_index(unsigned index, struct hso_serial *serial)
{
    unsigned long flags;

    spin_lock_irqsave(&serial_table_lock, flags);
    if (serial)
        serial_table[index] = serial->parent;
    else
        serial_table[index] = NULL;
    spin_unlock_irqrestore(&serial_table_lock, flags);
}

static void handle_usb_error(int status, const char *function,
                 struct hso_device *hso_dev)
{
    char *explanation;

    switch (status) {
    case -ENODEV:
        explanation = "no device";
        break;
    case -ENOENT:
        explanation = "endpoint not enabled";
        break;
    case -EPIPE:
        explanation = "endpoint stalled";
        break;
    case -ENOSPC:
        explanation = "not enough bandwidth";
        break;
    case -ESHUTDOWN:
        explanation = "device disabled";
        break;
    case -EHOSTUNREACH:
        explanation = "device suspended";
        break;
    case -EINVAL:
    case -EAGAIN:
    case -EFBIG:
    case -EMSGSIZE:
        explanation = "internal error";
        break;
    case -EILSEQ:
    case -EPROTO:
    case -ETIME:
    case -ETIMEDOUT:
        explanation = "protocol error";
        if (hso_dev)
            schedule_work(&hso_dev->reset_device);
        break;
    default:
        explanation = "unknown status";
        break;
    }

    /* log a meaningful explanation of an USB status */
    D1("%s: received USB status - %s (%d)", function, explanation, status);
}

/* Network interface functions */

/* called when net interface is brought up by ifconfig */
static int hso_net_open(struct net_device *net)
{
    struct hso_net *odev = netdev_priv(net);
    unsigned long flags = 0;

    if (!odev) {
        dev_err(&net->dev, "No net device !\n");
        return -ENODEV;
    }

    odev->skb_tx_buf = NULL;

    /* setup environment */
    spin_lock_irqsave(&odev->net_lock, flags);
    odev->rx_parse_state = WAIT_IP;
    odev->rx_buf_size = 0;
    odev->rx_buf_missing = sizeof(struct iphdr);
    spin_unlock_irqrestore(&odev->net_lock, flags);

    /* We are up and running. */
    set_bit(HSO_NET_RUNNING, &odev->flags);
    hso_start_net_device(odev->parent);

    /* Tell the kernel we are ready to start receiving from it */
    netif_start_queue(net);

    return 0;
}

/* called when interface is brought down by ifconfig */
static int hso_net_close(struct net_device *net)
{
    struct hso_net *odev = netdev_priv(net);

    /* we don't need the queue anymore */
    netif_stop_queue(net);
    /* no longer running */
    clear_bit(HSO_NET_RUNNING, &odev->flags);

    hso_stop_net_device(odev->parent);

    /* done */
    return 0;
}

/* USB tells is xmit done, we should start the netqueue again */
static void write_bulk_callback(struct urb *urb)
{
    struct hso_net *odev = urb->context;
    int status = urb->status;

    /* Sanity check */
    if (!odev || !test_bit(HSO_NET_RUNNING, &odev->flags)) {
        dev_err(&urb->dev->dev, "%s: device not running\n", __func__);
        return;
    }

    /* Do we still have a valid kernel network device? */
    if (!netif_device_present(odev->net)) {
        dev_err(&urb->dev->dev, "%s: net device not present\n",
            __func__);
        return;
    }

    /* log status, but don't act on it, we don't need to resubmit anything
     * anyhow */
    if (status)
        handle_usb_error(status, __func__, odev->parent);

    hso_put_activity(odev->parent);

    /* Tell the network interface we are ready for another frame */
    netif_wake_queue(odev->net);
}

/* called by kernel when we need to transmit a packet */
static netdev_tx_t hso_net_start_xmit(struct sk_buff *skb,
                        struct net_device *net)
{
    struct hso_net *odev = netdev_priv(net);
    int result;

    /* Tell the kernel, "No more frames 'til we are done with this one." */
    netif_stop_queue(net);
    if (hso_get_activity(odev->parent) == -EAGAIN) {
        odev->skb_tx_buf = skb;
        return NETDEV_TX_OK;
    }

    /* log if asked */
    DUMP1(skb->data, skb->len);
    /* Copy it from kernel memory to OUR memory */
    memcpy(odev->mux_bulk_tx_buf, skb->data, skb->len);
    D1("len: %d/%d", skb->len, MUX_BULK_TX_BUF_SIZE);

    /* Fill in the URB for shipping it out. */
    usb_fill_bulk_urb(odev->mux_bulk_tx_urb,
              odev->parent->usb,
              usb_sndbulkpipe(odev->parent->usb,
                      odev->out_endp->
                      bEndpointAddress & 0x7F),
              odev->mux_bulk_tx_buf, skb->len, write_bulk_callback,
              odev);

    /* Deal with the Zero Length packet problem, I hope */
    odev->mux_bulk_tx_urb->transfer_flags |= URB_ZERO_PACKET;

    /* Send the URB on its merry way. */
    result = usb_submit_urb(odev->mux_bulk_tx_urb, GFP_ATOMIC);
    if (result) {
        dev_warn(&odev->parent->interface->dev,
            "failed mux_bulk_tx_urb %d\n", result);
        net->stats.tx_errors++;
        netif_start_queue(net);
    } else {
        net->stats.tx_packets++;
        net->stats.tx_bytes += skb->len;
    }
    dev_kfree_skb(skb);
    /* we're done */
    return NETDEV_TX_OK;
}

static const struct ethtool_ops ops = {
    .get_link = ethtool_op_get_link
};

/* called when a packet did not ack after watchdogtimeout */
static void hso_net_tx_timeout(struct net_device *net)
{
    struct hso_net *odev = netdev_priv(net);

    if (!odev)
        return;

    /* Tell syslog we are hosed. */
    dev_warn(&net->dev, "Tx timed out.\n");

    /* Tear the waiting frame off the list */
    if (odev->mux_bulk_tx_urb &&
        (odev->mux_bulk_tx_urb->status == -EINPROGRESS))
        usb_unlink_urb(odev->mux_bulk_tx_urb);

    /* Update statistics */
    net->stats.tx_errors++;
}

/* make a real packet from the received USB buffer */
static void packetizeRx(struct hso_net *odev, unsigned char *ip_pkt,
            unsigned int count, unsigned char is_eop)
{
    unsigned short temp_bytes;
    unsigned short buffer_offset = 0;
    unsigned short frame_len;
    unsigned char *tmp_rx_buf;

    /* log if needed */
    D1("Rx %d bytes", count);
    DUMP(ip_pkt, min(128, (int)count));

    while (count) {
        switch (odev->rx_parse_state) {
        case WAIT_IP:
            /* waiting for IP header. */
            /* wanted bytes - size of ip header */
            temp_bytes =
                (count <
                 odev->rx_buf_missing) ? count : odev->
                rx_buf_missing;

            memcpy(((unsigned char *)(&odev->rx_ip_hdr)) +
                   odev->rx_buf_size, ip_pkt + buffer_offset,
                   temp_bytes);

            odev->rx_buf_size += temp_bytes;
            buffer_offset += temp_bytes;
            odev->rx_buf_missing -= temp_bytes;
            count -= temp_bytes;

            if (!odev->rx_buf_missing) {
                /* header is complete allocate an sk_buffer and
                 * continue to WAIT_DATA */
                frame_len = ntohs(odev->rx_ip_hdr.tot_len);

                if ((frame_len > DEFAULT_MRU) ||
                    (frame_len < sizeof(struct iphdr))) {
                    dev_err(&odev->net->dev,
                        "Invalid frame (%d) length\n",
                        frame_len);
                    odev->rx_parse_state = WAIT_SYNC;
                    continue;
                }
                /* Allocate an sk_buff */
                odev->skb_rx_buf = netdev_alloc_skb(odev->net,
                                    frame_len);
                if (!odev->skb_rx_buf) {
                    /* We got no receive buffer. */
                    D1("could not allocate memory");
                    odev->rx_parse_state = WAIT_SYNC;
                    return;
                }

                /* Copy what we got so far. make room for iphdr
                 * after tail. */
                tmp_rx_buf =
                    skb_put(odev->skb_rx_buf,
                        sizeof(struct iphdr));
                memcpy(tmp_rx_buf, (char *)&(odev->rx_ip_hdr),
                       sizeof(struct iphdr));

                /* ETH_HLEN */
                odev->rx_buf_size = sizeof(struct iphdr);

                /* Filip actually use .tot_len */
                odev->rx_buf_missing =
                    frame_len - sizeof(struct iphdr);
                odev->rx_parse_state = WAIT_DATA;
            }
            break;

        case WAIT_DATA:
            temp_bytes = (count < odev->rx_buf_missing)
                    ? count : odev->rx_buf_missing;

            /* Copy the rest of the bytes that are left in the
             * buffer into the waiting sk_buf. */
            /* Make room for temp_bytes after tail. */
            tmp_rx_buf = skb_put(odev->skb_rx_buf, temp_bytes);
            memcpy(tmp_rx_buf, ip_pkt + buffer_offset, temp_bytes);

            odev->rx_buf_missing -= temp_bytes;
            count -= temp_bytes;
            buffer_offset += temp_bytes;
            odev->rx_buf_size += temp_bytes;
            if (!odev->rx_buf_missing) {
                /* Packet is complete. Inject into stack. */
                /* We have IP packet here */
                odev->skb_rx_buf->protocol = cpu_to_be16(ETH_P_IP);
                skb_reset_mac_header(odev->skb_rx_buf);

                /* Ship it off to the kernel */
                netif_rx(odev->skb_rx_buf);
                /* No longer our buffer. */
                odev->skb_rx_buf = NULL;

                /* update out statistics */
                odev->net->stats.rx_packets++;

                odev->net->stats.rx_bytes += odev->rx_buf_size;

                odev->rx_buf_size = 0;
                odev->rx_buf_missing = sizeof(struct iphdr);
                odev->rx_parse_state = WAIT_IP;
            }
            break;

        case WAIT_SYNC:
            D1(" W_S");
            count = 0;
            break;
        default:
            D1(" ");
            count--;
            break;
        }
    }

    /* Recovery mechanism for WAIT_SYNC state. */
    if (is_eop) {
        if (odev->rx_parse_state == WAIT_SYNC) {
            odev->rx_parse_state = WAIT_IP;
            odev->rx_buf_size = 0;
            odev->rx_buf_missing = sizeof(struct iphdr);
        }
    }
}

static void fix_crc_bug(struct urb *urb, __le16 max_packet_size)
{
    static const u8 crc_check[4] = { 0xDE, 0xAD, 0xBE, 0xEF };
    u32 rest = urb->actual_length % le16_to_cpu(max_packet_size);

    if (((rest == 5) || (rest == 6)) &&
        !memcmp(((u8 *)urb->transfer_buffer) + urb->actual_length - 4,
            crc_check, 4)) {
        urb->actual_length -= 4;
    }
}

/* Moving data from usb to kernel (in interrupt state) */
static void read_bulk_callback(struct urb *urb)
{
    struct hso_net *odev = urb->context;
    struct net_device *net;
    int result;
    int status = urb->status;

    /* is al ok?  (Filip: Who's Al ?) */
    if (status) {
        handle_usb_error(status, __func__, odev->parent);
        return;
    }

    /* Sanity check */
    if (!odev || !test_bit(HSO_NET_RUNNING, &odev->flags)) {
        D1("BULK IN callback but driver is not active!");
        return;
    }
    usb_mark_last_busy(urb->dev);

    net = odev->net;

    if (!netif_device_present(net)) {
        /* Somebody killed our network interface... */
        return;
    }

    if (odev->parent->port_spec & HSO_INFO_CRC_BUG)
        fix_crc_bug(urb, odev->in_endp->wMaxPacketSize);

    /* do we even have a packet? */
    if (urb->actual_length) {
        /* Handle the IP stream, add header and push it onto network
         * stack if the packet is complete. */
        spin_lock(&odev->net_lock);
        packetizeRx(odev, urb->transfer_buffer, urb->actual_length,
                (urb->transfer_buffer_length >
                 urb->actual_length) ? 1 : 0);
        spin_unlock(&odev->net_lock);
    }

    /* We are done with this URB, resubmit it. Prep the USB to wait for
     * another frame. Reuse same as received. */
    usb_fill_bulk_urb(urb,
              odev->parent->usb,
              usb_rcvbulkpipe(odev->parent->usb,
                      odev->in_endp->
                      bEndpointAddress & 0x7F),
              urb->transfer_buffer, MUX_BULK_RX_BUF_SIZE,
              read_bulk_callback, odev);

    /* Give this to the USB subsystem so it can tell us when more data
     * arrives. */
    result = usb_submit_urb(urb, GFP_ATOMIC);
    if (result)
        dev_warn(&odev->parent->interface->dev,
             "%s failed submit mux_bulk_rx_urb %d\n", __func__,
             result);
}

/* Serial driver functions */

static void hso_init_termios(struct ktermios *termios)
{
    /*
     * The default requirements for this device are:
     */
    termios->c_iflag &=
        ~(IGNBRK    /* disable ignore break */
        | BRKINT    /* disable break causes interrupt */
        | PARMRK    /* disable mark parity errors */
        | ISTRIP    /* disable clear high bit of input characters */
        | INLCR     /* disable translate NL to CR */
        | IGNCR     /* disable ignore CR */
        | ICRNL     /* disable translate CR to NL */
        | IXON);    /* disable enable XON/XOFF flow control */

    /* disable postprocess output characters */
    termios->c_oflag &= ~OPOST;

    termios->c_lflag &=
        ~(ECHO      /* disable echo input characters */
        | ECHONL    /* disable echo new line */
        | ICANON    /* disable erase, kill, werase, and rprnt
                   special characters */
        | ISIG      /* disable interrupt, quit, and suspend special
                   characters */
        | IEXTEN);  /* disable non-POSIX special characters */

    termios->c_cflag &=
        ~(CSIZE     /* no size */
        | PARENB    /* disable parity bit */
        | CBAUD     /* clear current baud rate */
        | CBAUDEX); /* clear current buad rate */

    termios->c_cflag |= CS8;    /* character size 8 bits */

    /* baud rate 115200 */
    tty_termios_encode_baud_rate(termios, 115200, 115200);
}

static void _hso_serial_set_termios(struct tty_struct *tty,
                    struct ktermios *old)
{
    struct hso_serial *serial = tty->driver_data;

    if (!serial) {
        printk(KERN_ERR "%s: no tty structures", __func__);
        return;
    }

    D4("port %d", serial->minor);

    /*
     *  Fix up unsupported bits
     */
    tty->termios.c_iflag &= ~IXON; /* disable enable XON/XOFF flow control */

    tty->termios.c_cflag &=
        ~(CSIZE     /* no size */
        | PARENB    /* disable parity bit */
        | CBAUD     /* clear current baud rate */
        | CBAUDEX); /* clear current buad rate */

    tty->termios.c_cflag |= CS8;    /* character size 8 bits */

    /* baud rate 115200 */
    tty_encode_baud_rate(tty, 115200, 115200);
}

static void hso_resubmit_rx_bulk_urb(struct hso_serial *serial, struct urb *urb)
{
    int result;
    /* We are done with this URB, resubmit it. Prep the USB to wait for
     * another frame */
    usb_fill_bulk_urb(urb, serial->parent->usb,
              usb_rcvbulkpipe(serial->parent->usb,
                      serial->in_endp->
                      bEndpointAddress & 0x7F),
              urb->transfer_buffer, serial->rx_data_length,
              hso_std_serial_read_bulk_callback, serial);
    /* Give this to the USB subsystem so it can tell us when more data
     * arrives. */
    result = usb_submit_urb(urb, GFP_ATOMIC);
    if (result) {
        dev_err(&urb->dev->dev, "%s failed submit serial rx_urb %d\n",
            __func__, result);
    }
}




static void put_rxbuf_data_and_resubmit_bulk_urb(struct hso_serial *serial)
{
    int count;
    struct urb *curr_urb;

    while (serial->rx_urb_filled[serial->curr_rx_urb_idx]) {
        curr_urb = serial->rx_urb[serial->curr_rx_urb_idx];
        count = put_rxbuf_data(curr_urb, serial);
        if (count == -1)
            return;
        if (count == 0) {
            serial->curr_rx_urb_idx++;
            if (serial->curr_rx_urb_idx >= serial->num_rx_urbs)
                serial->curr_rx_urb_idx = 0;
            hso_resubmit_rx_bulk_urb(serial, curr_urb);
        }
    }
}

static void put_rxbuf_data_and_resubmit_ctrl_urb(struct hso_serial *serial)
{
    int count = 0;
    struct urb *urb;

    urb = serial->rx_urb[0];
    if (serial->port.count > 0) {
        count = put_rxbuf_data(urb, serial);
        if (count == -1)
            return;
    }
    /* Re issue a read as long as we receive data. */

    if (count == 0 && ((urb->actual_length != 0) ||
               (serial->rx_state == RX_PENDING))) {
        serial->rx_state = RX_SENT;
        hso_mux_serial_read(serial);
    } else
        serial->rx_state = RX_IDLE;
}


/* read callback for Diag and CS port */
static void hso_std_serial_read_bulk_callback(struct urb *urb)
{
    struct hso_serial *serial = urb->context;
    int status = urb->status;

    /* sanity check */
    if (!serial) {
        D1("serial == NULL");
        return;
    } else if (status) {
        handle_usb_error(status, __func__, serial->parent);
        return;
    }

    D4("\n--- Got serial_read_bulk callback %02x ---", status);
    D1("Actual length = %d\n", urb->actual_length);
    DUMP1(urb->transfer_buffer, urb->actual_length);

    /* Anyone listening? */
    if (serial->port.count == 0)
        return;

    if (status == 0) {
        if (serial->parent->port_spec & HSO_INFO_CRC_BUG)
            fix_crc_bug(urb, serial->in_endp->wMaxPacketSize);
        /* Valid data, handle RX data */
        spin_lock(&serial->serial_lock);
        serial->rx_urb_filled[hso_urb_to_index(serial, urb)] = 1;
        put_rxbuf_data_and_resubmit_bulk_urb(serial);
        spin_unlock(&serial->serial_lock);
    } else if (status == -ENOENT || status == -ECONNRESET) {
        /* Unlinked - check for throttled port. */
        D2("Port %d, successfully unlinked urb", serial->minor);
        spin_lock(&serial->serial_lock);
        serial->rx_urb_filled[hso_urb_to_index(serial, urb)] = 0;
        hso_resubmit_rx_bulk_urb(serial, urb);
        spin_unlock(&serial->serial_lock);
    } else {
        D2("Port %d, status = %d for read urb", serial->minor, status);
        return;
    }
}

/*
 * This needs to be a tasklet otherwise we will
 * end up recursively calling this function.
 */
static void hso_unthrottle_tasklet(struct hso_serial *serial)
{
    unsigned long flags;

    spin_lock_irqsave(&serial->serial_lock, flags);
    if ((serial->parent->port_spec & HSO_INTF_MUX))
        put_rxbuf_data_and_resubmit_ctrl_urb(serial);
    else
        put_rxbuf_data_and_resubmit_bulk_urb(serial);
    spin_unlock_irqrestore(&serial->serial_lock, flags);
}

static  void hso_unthrottle(struct tty_struct *tty)
{
    struct hso_serial *serial = tty->driver_data;

    tasklet_hi_schedule(&serial->unthrottle_tasklet);
}

static void hso_unthrottle_workfunc(struct work_struct *work)
{
    struct hso_serial *serial =
        container_of(work, struct hso_serial,
             retry_unthrottle_workqueue);
    hso_unthrottle_tasklet(serial);
}

/* open the requested serial port */
static int hso_serial_open(struct tty_struct *tty, struct file *filp)
{
    struct hso_serial *serial = get_serial_by_index(tty->index);
    int result;

    /* sanity check */
    if (serial == NULL || serial->magic != HSO_SERIAL_MAGIC) {
        WARN_ON(1);
        tty->driver_data = NULL;
        D1("Failed to open port");
        return -ENODEV;
    }

    mutex_lock(&serial->parent->mutex);
    result = usb_autopm_get_interface(serial->parent->interface);
    if (result < 0)
        goto err_out;

    D1("Opening %d", serial->minor);
    kref_get(&serial->parent->ref);

    /* setup */
    tty->driver_data = serial;
    tty_port_tty_set(&serial->port, tty);

    /* check for port already opened, if not set the termios */
    serial->port.count++;
    if (serial->port.count == 1) {
        serial->rx_state = RX_IDLE;
        /* Force default termio settings */
        _hso_serial_set_termios(tty, NULL);
        tasklet_init(&serial->unthrottle_tasklet,
                 (void (*)(unsigned long))hso_unthrottle_tasklet,
                 (unsigned long)serial);
        INIT_WORK(&serial->retry_unthrottle_workqueue,
              hso_unthrottle_workfunc);
        result = hso_start_serial_device(serial->parent, GFP_KERNEL);
        if (result) {
            hso_stop_serial_device(serial->parent);
            serial->port.count--;
            kref_put(&serial->parent->ref, hso_serial_ref_free);
        }
    } else {
        D1("Port was already open");
    }

    usb_autopm_put_interface(serial->parent->interface);

    /* done */
    if (result)
        hso_serial_tiocmset(tty, TIOCM_RTS | TIOCM_DTR, 0);
err_out:
    mutex_unlock(&serial->parent->mutex);
    return result;
}

/* close the requested serial port */
static void hso_serial_close(struct tty_struct *tty, struct file *filp)
{
    struct hso_serial *serial = tty->driver_data;
    u8 usb_gone;

    D1("Closing serial port");

    /* Open failed, no close cleanup required */
    if (serial == NULL)
        return;

    mutex_lock(&serial->parent->mutex);
    usb_gone = serial->parent->usb_gone;

    if (!usb_gone)
        usb_autopm_get_interface(serial->parent->interface);

    /* reset the rts and dtr */
    /* do the actual close */
    serial->port.count--;

    if (serial->port.count <= 0) {
        serial->port.count = 0;
        tty_port_tty_set(&serial->port, NULL);
        if (!usb_gone)
            hso_stop_serial_device(serial->parent);
        tasklet_kill(&serial->unthrottle_tasklet);
        cancel_work_sync(&serial->retry_unthrottle_workqueue);
    }

    if (!usb_gone)
        usb_autopm_put_interface(serial->parent->interface);

    mutex_unlock(&serial->parent->mutex);

    kref_put(&serial->parent->ref, hso_serial_ref_free);
}

/* close the requested serial port */
static int hso_serial_write(struct tty_struct *tty, const unsigned char *buf,
                int count)
{
    struct hso_serial *serial = tty->driver_data;
    int space, tx_bytes;
    unsigned long flags;

    /* sanity check */
    if (serial == NULL) {
        printk(KERN_ERR "%s: serial is NULL\n", __func__);
        return -ENODEV;
    }

    spin_lock_irqsave(&serial->serial_lock, flags);

    space = serial->tx_data_length - serial->tx_buffer_count;
    tx_bytes = (count < space) ? count : space;

    if (!tx_bytes)
        goto out;

    memcpy(serial->tx_buffer + serial->tx_buffer_count, buf, tx_bytes);
    serial->tx_buffer_count += tx_bytes;

out:
    spin_unlock_irqrestore(&serial->serial_lock, flags);

    hso_kick_transmit(serial);
    /* done */
    return tx_bytes;
}

/* how much room is there for writing */
static int hso_serial_write_room(struct tty_struct *tty)
{
    struct hso_serial *serial = tty->driver_data;
    int room;
    unsigned long flags;

    spin_lock_irqsave(&serial->serial_lock, flags);
    room = serial->tx_data_length - serial->tx_buffer_count;
    spin_unlock_irqrestore(&serial->serial_lock, flags);

    /* return free room */
    return room;
}

/* setup the term */
static void hso_serial_set_termios(struct tty_struct *tty, struct ktermios *old)
{
    struct hso_serial *serial = tty->driver_data;
    unsigned long flags;

    if (old)
        D5("Termios called with: cflags new[%d] - old[%d]",
           tty->termios.c_cflag, old->c_cflag);

    /* the actual setup */
    spin_lock_irqsave(&serial->serial_lock, flags);
    if (serial->port.count)
        _hso_serial_set_termios(tty, old);
    else
        tty->termios = *old;
    spin_unlock_irqrestore(&serial->serial_lock, flags);

    /* done */
}

/* how many characters in the buffer */
static int hso_serial_chars_in_buffer(struct tty_struct *tty)
{
    struct hso_serial *serial = tty->driver_data;
    int chars;
    unsigned long flags;

    /* sanity check */
    if (serial == NULL)
        return 0;

    spin_lock_irqsave(&serial->serial_lock, flags);
    chars = serial->tx_buffer_count;
    spin_unlock_irqrestore(&serial->serial_lock, flags);

    return chars;
}
static int tiocmget_submit_urb(struct hso_serial *serial,
                   struct hso_tiocmget *tiocmget,
                   struct usb_device *usb)
{
    int result;

    if (serial->parent->usb_gone)
        return -ENODEV;
    usb_fill_int_urb(tiocmget->urb, usb,
             usb_rcvintpipe(usb,
                    tiocmget->endp->
                    bEndpointAddress & 0x7F),
             &tiocmget->serial_state_notification,
             sizeof(struct hso_serial_state_notification),
             tiocmget_intr_callback, serial,
             tiocmget->endp->bInterval);
    result = usb_submit_urb(tiocmget->urb, GFP_ATOMIC);
    if (result) {
        dev_warn(&usb->dev, "%s usb_submit_urb failed %d\n", __func__,
             result);
    }
    return result;

}

static void tiocmget_intr_callback(struct urb *urb)
{
    struct hso_serial *serial = urb->context;
    struct hso_tiocmget *tiocmget;
    int status = urb->status;
    u16 UART_state_bitmap, prev_UART_state_bitmap;
    struct uart_icount *icount;
    struct hso_serial_state_notification *serial_state_notification;
    struct usb_device *usb;

    /* Sanity checks */
    if (!serial)
        return;
    if (status) {
        handle_usb_error(status, __func__, serial->parent);
        return;
    }
    tiocmget = serial->tiocmget;
    if (!tiocmget)
        return;
    usb = serial->parent->usb;
    serial_state_notification = &tiocmget->serial_state_notification;
    if (serial_state_notification->bmRequestType != BM_REQUEST_TYPE ||
        serial_state_notification->bNotification != B_NOTIFICATION ||
        le16_to_cpu(serial_state_notification->wValue) != W_VALUE ||
        le16_to_cpu(serial_state_notification->wIndex) != W_INDEX ||
        le16_to_cpu(serial_state_notification->wLength) != W_LENGTH) {
        dev_warn(&usb->dev,
             "hso received invalid serial state notification\n");
        DUMP(serial_state_notification,
             sizeof(struct hso_serial_state_notification));
    } else {

        UART_state_bitmap = le16_to_cpu(serial_state_notification->
                        UART_state_bitmap);
        prev_UART_state_bitmap = tiocmget->prev_UART_state_bitmap;
        icount = &tiocmget->icount;
        spin_lock(&serial->serial_lock);
        if ((UART_state_bitmap & B_OVERRUN) !=
           (prev_UART_state_bitmap & B_OVERRUN))
            icount->parity++;
        if ((UART_state_bitmap & B_PARITY) !=
           (prev_UART_state_bitmap & B_PARITY))
            icount->parity++;
        if ((UART_state_bitmap & B_FRAMING) !=
           (prev_UART_state_bitmap & B_FRAMING))
            icount->frame++;
        if ((UART_state_bitmap & B_RING_SIGNAL) &&
           !(prev_UART_state_bitmap & B_RING_SIGNAL))
            icount->rng++;
        if ((UART_state_bitmap & B_BREAK) !=
           (prev_UART_state_bitmap & B_BREAK))
            icount->brk++;
        if ((UART_state_bitmap & B_TX_CARRIER) !=
           (prev_UART_state_bitmap & B_TX_CARRIER))
            icount->dsr++;
        if ((UART_state_bitmap & B_RX_CARRIER) !=
           (prev_UART_state_bitmap & B_RX_CARRIER))
            icount->dcd++;
        tiocmget->prev_UART_state_bitmap = UART_state_bitmap;
        spin_unlock(&serial->serial_lock);
        tiocmget->intr_completed = 1;
        wake_up_interruptible(&tiocmget->waitq);
    }
    memset(serial_state_notification, 0,
           sizeof(struct hso_serial_state_notification));
    tiocmget_submit_urb(serial,
                tiocmget,
                serial->parent->usb);
}

/*
 * next few functions largely stolen from drivers/serial/serial_core.c
 */
/* Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
 * - mask passed in arg for lines of interest
 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
 * Caller should use TIOCGICOUNT to see which one it was
 */
static int
hso_wait_modem_status(struct hso_serial *serial, unsigned long arg)
{
    DECLARE_WAITQUEUE(wait, current);
    struct uart_icount cprev, cnow;
    struct hso_tiocmget  *tiocmget;
    int ret;

    tiocmget = serial->tiocmget;
    if (!tiocmget)
        return -ENOENT;
    /*
     * note the counters on entry
     */
    spin_lock_irq(&serial->serial_lock);
    memcpy(&cprev, &tiocmget->icount, sizeof(struct uart_icount));
    spin_unlock_irq(&serial->serial_lock);
    add_wait_queue(&tiocmget->waitq, &wait);
    for (;;) {
        spin_lock_irq(&serial->serial_lock);
        memcpy(&cnow, &tiocmget->icount, sizeof(struct uart_icount));
        spin_unlock_irq(&serial->serial_lock);
        set_current_state(TASK_INTERRUPTIBLE);
        if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
            ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
            ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd))) {
            ret = 0;
            break;
        }
        schedule();
        /* see if a signal did it */
        if (signal_pending(current)) {
            ret = -ERESTARTSYS;
            break;
        }
        cprev = cnow;
    }
    current->state = TASK_RUNNING;
    remove_wait_queue(&tiocmget->waitq, &wait);

    return ret;
}

/*
 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
 * Return: write counters to the user passed counter struct
 * NB: both 1->0 and 0->1 transitions are counted except for
 *     RI where only 0->1 is counted.
 */
static int hso_get_count(struct tty_struct *tty,
          struct serial_icounter_struct *icount)
{
    struct uart_icount cnow;
    struct hso_serial *serial = tty->driver_data;
    struct hso_tiocmget  *tiocmget = serial->tiocmget;

    memset(icount, 0, sizeof(struct serial_icounter_struct));

    if (!tiocmget)
         return -ENOENT;
    spin_lock_irq(&serial->serial_lock);
    memcpy(&cnow, &tiocmget->icount, sizeof(struct uart_icount));
    spin_unlock_irq(&serial->serial_lock);

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

    return 0;
}


static int hso_serial_tiocmget(struct tty_struct *tty)
{
    int retval;
    struct hso_serial *serial = tty->driver_data;
    struct hso_tiocmget  *tiocmget;
    u16 UART_state_bitmap;

    /* sanity check */
    if (!serial) {
        D1("no tty structures");
        return -EINVAL;
    }
    spin_lock_irq(&serial->serial_lock);
    retval = ((serial->rts_state) ? TIOCM_RTS : 0) |
        ((serial->dtr_state) ? TIOCM_DTR : 0);
    tiocmget = serial->tiocmget;
    if (tiocmget) {

        UART_state_bitmap = le16_to_cpu(
            tiocmget->prev_UART_state_bitmap);
        if (UART_state_bitmap & B_RING_SIGNAL)
            retval |=  TIOCM_RNG;
        if (UART_state_bitmap & B_RX_CARRIER)
            retval |=  TIOCM_CD;
        if (UART_state_bitmap & B_TX_CARRIER)
            retval |=  TIOCM_DSR;
    }
    spin_unlock_irq(&serial->serial_lock);
    return retval;
}

static int hso_serial_tiocmset(struct tty_struct *tty,
                   unsigned int set, unsigned int clear)
{
    int val = 0;
    unsigned long flags;
    int if_num;
    struct hso_serial *serial = tty->driver_data;

    /* sanity check */
    if (!serial) {
        D1("no tty structures");
        return -EINVAL;
    }

    if ((serial->parent->port_spec & HSO_PORT_MASK) != HSO_PORT_MODEM)
        return -EINVAL;

    if_num = serial->parent->interface->altsetting->desc.bInterfaceNumber;

    spin_lock_irqsave(&serial->serial_lock, flags);
    if (set & TIOCM_RTS)
        serial->rts_state = 1;
    if (set & TIOCM_DTR)
        serial->dtr_state = 1;

    if (clear & TIOCM_RTS)
        serial->rts_state = 0;
    if (clear & TIOCM_DTR)
        serial->dtr_state = 0;

    if (serial->dtr_state)
        val |= 0x01;
    if (serial->rts_state)
        val |= 0x02;

    spin_unlock_irqrestore(&serial->serial_lock, flags);

    return usb_control_msg(serial->parent->usb,
                   usb_rcvctrlpipe(serial->parent->usb, 0), 0x22,
                   0x21, val, if_num, NULL, 0,
                   USB_CTRL_SET_TIMEOUT);
}

static int hso_serial_ioctl(struct tty_struct *tty,
                unsigned int cmd, unsigned long arg)
{
    struct hso_serial *serial = tty->driver_data;
    int ret = 0;
    D4("IOCTL cmd: %d, arg: %ld", cmd, arg);

    if (!serial)
        return -ENODEV;
    switch (cmd) {
    case TIOCMIWAIT:
        ret = hso_wait_modem_status(serial, arg);
        break;
    default:
        ret = -ENOIOCTLCMD;
        break;
    }
    return ret;
}


/* starts a transmit */
static void hso_kick_transmit(struct hso_serial *serial)
{
    u8 *temp;
    unsigned long flags;
    int res;

    spin_lock_irqsave(&serial->serial_lock, flags);
    if (!serial->tx_buffer_count)
        goto out;

    if (serial->tx_urb_used)
        goto out;

    /* Wakeup USB interface if necessary */
    if (hso_get_activity(serial->parent) == -EAGAIN)
        goto out;

    /* Switch pointers around to avoid memcpy */
    temp = serial->tx_buffer;
    serial->tx_buffer = serial->tx_data;
    serial->tx_data = temp;
    serial->tx_data_count = serial->tx_buffer_count;
    serial->tx_buffer_count = 0;

    /* If temp is set, it means we switched buffers */
    if (temp && serial->write_data) {
        res = serial->write_data(serial);
        if (res >= 0)
            serial->tx_urb_used = 1;
    }
out:
    spin_unlock_irqrestore(&serial->serial_lock, flags);
}

/* make a request (for reading and writing data to muxed serial port) */
static int mux_device_request(struct hso_serial *serial, u8 type, u16 port,
                  struct urb *ctrl_urb,
                  struct usb_ctrlrequest *ctrl_req,
                  u8 *ctrl_urb_data, u32 size)
{
    int result;
    int pipe;

    /* Sanity check */
    if (!serial || !ctrl_urb || !ctrl_req) {
        printk(KERN_ERR "%s: Wrong arguments\n", __func__);
        return -EINVAL;
    }

    /* initialize */
    ctrl_req->wValue = 0;
    ctrl_req->wIndex = cpu_to_le16(hso_port_to_mux(port));
    ctrl_req->wLength = cpu_to_le16(size);

    if (type == USB_CDC_GET_ENCAPSULATED_RESPONSE) {
        /* Reading command */
        ctrl_req->bRequestType = USB_DIR_IN |
                     USB_TYPE_OPTION_VENDOR |
                     USB_RECIP_INTERFACE;
        ctrl_req->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE;
        pipe = usb_rcvctrlpipe(serial->parent->usb, 0);
    } else {
        /* Writing command */
        ctrl_req->bRequestType = USB_DIR_OUT |
                     USB_TYPE_OPTION_VENDOR |
                     USB_RECIP_INTERFACE;
        ctrl_req->bRequest = USB_CDC_SEND_ENCAPSULATED_COMMAND;
        pipe = usb_sndctrlpipe(serial->parent->usb, 0);
    }
    /* syslog */
    D2("%s command (%02x) len: %d, port: %d",
       type == USB_CDC_GET_ENCAPSULATED_RESPONSE ? "Read" : "Write",
       ctrl_req->bRequestType, ctrl_req->wLength, port);

    /* Load ctrl urb */
    ctrl_urb->transfer_flags = 0;
    usb_fill_control_urb(ctrl_urb,
                 serial->parent->usb,
                 pipe,
                 (u8 *) ctrl_req,
                 ctrl_urb_data, size, ctrl_callback, serial);
    /* Send it on merry way */
    result = usb_submit_urb(ctrl_urb, GFP_ATOMIC);
    if (result) {
        dev_err(&ctrl_urb->dev->dev,
            "%s failed submit ctrl_urb %d type %d\n", __func__,
            result, type);
        return result;
    }

    /* done */
    return size;
}

/* called by intr_callback when read occurs */
static int hso_mux_serial_read(struct hso_serial *serial)
{
    if (!serial)
        return -EINVAL;

    /* clean data */
    memset(serial->rx_data[0], 0, CTRL_URB_RX_SIZE);
    /* make the request */

    if (serial->num_rx_urbs != 1) {
        dev_err(&serial->parent->interface->dev,
            "ERROR: mux'd reads with multiple buffers "
            "not possible\n");
        return 0;
    }
    return mux_device_request(serial,
                  USB_CDC_GET_ENCAPSULATED_RESPONSE,
                  serial->parent->port_spec & HSO_PORT_MASK,
                  serial->rx_urb[0],
                  &serial->ctrl_req_rx,
                  serial->rx_data[0], serial->rx_data_length);
}

/* used for muxed serial port callback (muxed serial read) */
static void intr_callback(struct urb *urb)
{
    struct hso_shared_int *shared_int = urb->context;
    struct hso_serial *serial;
    unsigned char *port_req;
    int status = urb->status;
    int i;

    usb_mark_last_busy(urb->dev);

    /* sanity check */
    if (!shared_int)
        return;

    /* status check */
    if (status) {
        handle_usb_error(status, __func__, NULL);
        return;
    }
    D4("\n--- Got intr callback 0x%02X ---", status);

    /* what request? */
    port_req = urb->transfer_buffer;
    D4(" port_req = 0x%.2X\n", *port_req);
    /* loop over all muxed ports to find the one sending this */
    for (i = 0; i < 8; i++) {
        /* max 8 channels on MUX */
        if (*port_req & (1 << i)) {
            serial = get_serial_by_shared_int_and_type(shared_int,
                                   (1 << i));
            if (serial != NULL) {
                D1("Pending read interrupt on port %d\n", i);
                spin_lock(&serial->serial_lock);
                if (serial->rx_state == RX_IDLE &&
                    serial->port.count > 0) {
                    /* Setup and send a ctrl req read on
                     * port i */
                    if (!serial->rx_urb_filled[0]) {
                        serial->rx_state = RX_SENT;
                        hso_mux_serial_read(serial);
                    } else
                        serial->rx_state = RX_PENDING;
                } else {
                    D1("Already a read pending on "
                       "port %d or port not open\n", i);
                }
                spin_unlock(&serial->serial_lock);
            }
        }
    }
    /* Resubmit interrupt urb */
    hso_mux_submit_intr_urb(shared_int, urb->dev, GFP_ATOMIC);
}

/* called for writing to muxed serial port */
static int hso_mux_serial_write_data(struct hso_serial *serial)
{
    if (NULL == serial)
        return -EINVAL;

    return mux_device_request(serial,
                  USB_CDC_SEND_ENCAPSULATED_COMMAND,
                  serial->parent->port_spec & HSO_PORT_MASK,
                  serial->tx_urb,
                  &serial->ctrl_req_tx,
                  serial->tx_data, serial->tx_data_count);
}

/* write callback for Diag and CS port */
static void hso_std_serial_write_bulk_callback(struct urb *urb)
{
    struct hso_serial *serial = urb->context;
    int status = urb->status;
    struct tty_struct *tty;

    /* sanity check */
    if (!serial) {
        D1("serial == NULL");
        return;
    }

    spin_lock(&serial->serial_lock);
    serial->tx_urb_used = 0;
    spin_unlock(&serial->serial_lock);
    if (status) {
        handle_usb_error(status, __func__, serial->parent);
        return;
    }
    hso_put_activity(serial->parent);
    tty = tty_port_tty_get(&serial->port);
    if (tty) {
        tty_wakeup(tty);
        tty_kref_put(tty);
    }
    hso_kick_transmit(serial);

    D1(" ");
}

/* called for writing diag or CS serial port */
static int hso_std_serial_write_data(struct hso_serial *serial)
{
    int count = serial->tx_data_count;
    int result;

    usb_fill_bulk_urb(serial->tx_urb,
              serial->parent->usb,
              usb_sndbulkpipe(serial->parent->usb,
                      serial->out_endp->
                      bEndpointAddress & 0x7F),
              serial->tx_data, serial->tx_data_count,
              hso_std_serial_write_bulk_callback, serial);

    result = usb_submit_urb(serial->tx_urb, GFP_ATOMIC);
    if (result) {
        dev_warn(&serial->parent->usb->dev,
             "Failed to submit urb - res %d\n", result);
        return result;
    }

    return count;
}

/* callback after read or write on muxed serial port */
static void ctrl_callback(struct urb *urb)
{
    struct hso_serial *serial = urb->context;
    struct usb_ctrlrequest *req;
    int status = urb->status;

    /* sanity check */
    if (!serial)
        return;

    spin_lock(&serial->serial_lock);
    serial->tx_urb_used = 0;
    spin_unlock(&serial->serial_lock);
    if (status) {
        handle_usb_error(status, __func__, serial->parent);
        return;
    }

    /* what request? */
    req = (struct usb_ctrlrequest *)(urb->setup_packet);
    D4("\n--- Got muxed ctrl callback 0x%02X ---", status);
    D4("Actual length of urb = %d\n", urb->actual_length);
    DUMP1(urb->transfer_buffer, urb->actual_length);

    if (req->bRequestType ==
        (USB_DIR_IN | USB_TYPE_OPTION_VENDOR | USB_RECIP_INTERFACE)) {
        /* response to a read command */
        serial->rx_urb_filled[0] = 1;
        spin_lock(&serial->serial_lock);
        put_rxbuf_data_and_resubmit_ctrl_urb(serial);
        spin_unlock(&serial->serial_lock);
    } else {
        struct tty_struct *tty = tty_port_tty_get(&serial->port);
        hso_put_activity(serial->parent);
        if (tty) {
            tty_wakeup(tty);
            tty_kref_put(tty);
        }
        /* response to a write command */
        hso_kick_transmit(serial);
    }
}

/* handle RX data for serial port */
static int put_rxbuf_data(struct urb *urb, struct hso_serial *serial)
{
    struct tty_struct *tty;
    int write_length_remaining = 0;
    int curr_write_len;

    /* Sanity check */
    if (urb == NULL || serial == NULL) {
        D1("serial = NULL");
        return -2;
    }

    tty = tty_port_tty_get(&serial->port);

    /* Push data to tty */
    if (tty) {
        write_length_remaining = urb->actual_length -
            serial->curr_rx_urb_offset;
        D1("data to push to tty");
        while (write_length_remaining) {
            if (test_bit(TTY_THROTTLED, &tty->flags)) {
                tty_kref_put(tty);
                return -1;
            }
            curr_write_len =  tty_insert_flip_string
                (tty, urb->transfer_buffer +
                 serial->curr_rx_urb_offset,
                 write_length_remaining);
            serial->curr_rx_urb_offset += curr_write_len;
            write_length_remaining -= curr_write_len;
            tty_flip_buffer_push(tty);
        }
        tty_kref_put(tty);
    }
    if (write_length_remaining == 0) {
        serial->curr_rx_urb_offset = 0;
        serial->rx_urb_filled[hso_urb_to_index(serial, urb)] = 0;
    }
    return write_length_remaining;
}


/* Base driver functions */

static void hso_log_port(struct hso_device *hso_dev)
{
    char *port_type;
    char port_dev[20];

    switch (hso_dev->port_spec & HSO_PORT_MASK) {
    case HSO_PORT_CONTROL:
        port_type = "Control";
        break;
    case HSO_PORT_APP:
        port_type = "Application";
        break;
    case HSO_PORT_GPS:
        port_type = "GPS";
        break;
    case HSO_PORT_GPS_CONTROL:
        port_type = "GPS control";
        break;
    case HSO_PORT_APP2:
        port_type = "Application2";
        break;
    case HSO_PORT_PCSC:
        port_type = "PCSC";
        break;
    case HSO_PORT_DIAG:
        port_type = "Diagnostic";
        break;
    case HSO_PORT_DIAG2:
        port_type = "Diagnostic2";
        break;
    case HSO_PORT_MODEM:
        port_type = "Modem";
        break;
    case HSO_PORT_NETWORK:
        port_type = "Network";
        break;
    default:
        port_type = "Unknown";
        break;
    }
    if ((hso_dev->port_spec & HSO_PORT_MASK) == HSO_PORT_NETWORK) {
        sprintf(port_dev, "%s", dev2net(hso_dev)->net->name);
    } else
        sprintf(port_dev, "/dev/%s%d", tty_filename,
            dev2ser(hso_dev)->minor);

    dev_dbg(&hso_dev->interface->dev, "HSO: Found %s port %s\n",
        port_type, port_dev);
}

static int hso_start_net_device(struct hso_device *hso_dev)
{
    int i, result = 0;
    struct hso_net *hso_net = dev2net(hso_dev);

    if (!hso_net)
        return -ENODEV;

    /* send URBs for all read buffers */
    for (i = 0; i < MUX_BULK_RX_BUF_COUNT; i++) {

        /* Prep a receive URB */
        usb_fill_bulk_urb(hso_net->mux_bulk_rx_urb_pool[i],
                  hso_dev->usb,
                  usb_rcvbulkpipe(hso_dev->usb,
                          hso_net->in_endp->
                          bEndpointAddress & 0x7F),
                  hso_net->mux_bulk_rx_buf_pool[i],
                  MUX_BULK_RX_BUF_SIZE, read_bulk_callback,
                  hso_net);

        /* Put it out there so the device can send us stuff */
        result = usb_submit_urb(hso_net->mux_bulk_rx_urb_pool[i],
                    GFP_NOIO);
        if (result)
            dev_warn(&hso_dev->usb->dev,
                "%s failed mux_bulk_rx_urb[%d] %d\n", __func__,
                i, result);
    }

    return result;
}

static int hso_stop_net_device(struct hso_device *hso_dev)
{
    int i;
    struct hso_net *hso_net = dev2net(hso_dev);

    if (!hso_net)
        return -ENODEV;

    for (i = 0; i < MUX_BULK_RX_BUF_COUNT; i++) {
        if (hso_net->mux_bulk_rx_urb_pool[i])
            usb_kill_urb(hso_net->mux_bulk_rx_urb_pool[i]);

    }
    if (hso_net->mux_bulk_tx_urb)
        usb_kill_urb(hso_net->mux_bulk_tx_urb);

    return 0;
}

static int hso_start_serial_device(struct hso_device *hso_dev, gfp_t flags)
{
    int i, result = 0;
    struct hso_serial *serial = dev2ser(hso_dev);

    if (!serial)
        return -ENODEV;

    /* If it is not the MUX port fill in and submit a bulk urb (already
     * allocated in hso_serial_start) */
    if (!(serial->parent->port_spec & HSO_INTF_MUX)) {
        for (i = 0; i < serial->num_rx_urbs; i++) {
            usb_fill_bulk_urb(serial->rx_urb[i],
                      serial->parent->usb,
                      usb_rcvbulkpipe(serial->parent->usb,
                              serial->in_endp->
                              bEndpointAddress &
                              0x7F),
                      serial->rx_data[i],
                      serial->rx_data_length,
                      hso_std_serial_read_bulk_callback,
                      serial);
            result = usb_submit_urb(serial->rx_urb[i], flags);
            if (result) {
                dev_warn(&serial->parent->usb->dev,
                     "Failed to submit urb - res %d\n",
                     result);
                break;
            }
        }
    } else {
        mutex_lock(&serial->shared_int->shared_int_lock);
        if (!serial->shared_int->use_count) {
            result =
                hso_mux_submit_intr_urb(serial->shared_int,
                            hso_dev->usb, flags);
        }
        serial->shared_int->use_count++;
        mutex_unlock(&serial->shared_int->shared_int_lock);
    }
    if (serial->tiocmget)
        tiocmget_submit_urb(serial,
                    serial->tiocmget,
                    serial->parent->usb);
    return result;
}

static int hso_stop_serial_device(struct hso_device *hso_dev)
{
    int i;
    struct hso_serial *serial = dev2ser(hso_dev);
    struct hso_tiocmget  *tiocmget;

    if (!serial)
        return -ENODEV;

    for (i = 0; i < serial->num_rx_urbs; i++) {
        if (serial->rx_urb[i]) {
                usb_kill_urb(serial->rx_urb[i]);
                serial->rx_urb_filled[i] = 0;
        }
    }
    serial->curr_rx_urb_idx = 0;
    serial->curr_rx_urb_offset = 0;

    if (serial->tx_urb)
        usb_kill_urb(serial->tx_urb);

    if (serial->shared_int) {
        mutex_lock(&serial->shared_int->shared_int_lock);
        if (serial->shared_int->use_count &&
            (--serial->shared_int->use_count == 0)) {
            struct urb *urb;

            urb = serial->shared_int->shared_intr_urb;
            if (urb)
                usb_kill_urb(urb);
        }
        mutex_unlock(&serial->shared_int->shared_int_lock);
    }
    tiocmget = serial->tiocmget;
    if (tiocmget) {
        wake_up_interruptible(&tiocmget->waitq);
        usb_kill_urb(tiocmget->urb);
    }

    return 0;
}

static void hso_serial_common_free(struct hso_serial *serial)
{
    int i;

    if (serial->parent->dev)
        device_remove_file(serial->parent->dev, &dev_attr_hsotype);

    tty_unregister_device(tty_drv, serial->minor);

    for (i = 0; i < serial->num_rx_urbs; i++) {
        /* unlink and free RX URB */
        usb_free_urb(serial->rx_urb[i]);
        /* free the RX buffer */
        kfree(serial->rx_data[i]);
    }

    /* unlink and free TX URB */
    usb_free_urb(serial->tx_urb);
    kfree(serial->tx_data);
}

static int hso_serial_common_create(struct hso_serial *serial, int num_urbs,
                    int rx_size, int tx_size)
{
    struct device *dev;
    int minor;
    int i;

    minor = get_free_serial_index();
    if (minor < 0)
        goto exit;

    tty_port_init(&serial->port);

    /* register our minor number */
    serial->parent->dev = tty_port_register_device(&serial->port, tty_drv,
            minor, &serial->parent->interface->dev);
    dev = serial->parent->dev;
    dev_set_drvdata(dev, serial->parent);
    i = device_create_file(dev, &dev_attr_hsotype);

    /* fill in specific data for later use */
    serial->minor = minor;
    serial->magic = HSO_SERIAL_MAGIC;
    spin_lock_init(&serial->serial_lock);
    serial->num_rx_urbs = num_urbs;

    /* RX, allocate urb and initialize */

    /* prepare our RX buffer */
    serial->rx_data_length = rx_size;
    for (i = 0; i < serial->num_rx_urbs; i++) {
        serial->rx_urb[i] = usb_alloc_urb(0, GFP_KERNEL);
        if (!serial->rx_urb[i]) {
            dev_err(dev, "Could not allocate urb?\n");
            goto exit;
        }
        serial->rx_urb[i]->transfer_buffer = NULL;
        serial->rx_urb[i]->transfer_buffer_length = 0;
        serial->rx_data[i] = kzalloc(serial->rx_data_length,
                         GFP_KERNEL);
        if (!serial->rx_data[i]) {
            dev_err(dev, "%s - Out of memory\n", __func__);
            goto exit;
        }
    }

    /* TX, allocate urb and initialize */
    serial->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
    if (!serial->tx_urb) {
        dev_err(dev, "Could not allocate urb?\n");
        goto exit;
    }
    serial->tx_urb->transfer_buffer = NULL;
    serial->tx_urb->transfer_buffer_length = 0;
    /* prepare our TX buffer */
    serial->tx_data_count = 0;
    serial->tx_buffer_count = 0;
    serial->tx_data_length = tx_size;
    serial->tx_data = kzalloc(serial->tx_data_length, GFP_KERNEL);
    if (!serial->tx_data) {
        dev_err(dev, "%s - Out of memory\n", __func__);
        goto exit;
    }
    serial->tx_buffer = kzalloc(serial->tx_data_length, GFP_KERNEL);
    if (!serial->tx_buffer) {
        dev_err(dev, "%s - Out of memory\n", __func__);
        goto exit;
    }

    return 0;
exit:
    hso_serial_common_free(serial);
    return -1;
}

/* Creates a general hso device */
static struct hso_device *hso_create_device(struct usb_interface *intf,
                        int port_spec)
{
    struct hso_device *hso_dev;

    hso_dev = kzalloc(sizeof(*hso_dev), GFP_ATOMIC);
    if (!hso_dev)
        return NULL;

    hso_dev->port_spec = port_spec;
    hso_dev->usb = interface_to_usbdev(intf);
    hso_dev->interface = intf;
    kref_init(&hso_dev->ref);
    mutex_init(&hso_dev->mutex);

    INIT_WORK(&hso_dev->async_get_intf, async_get_intf);
    INIT_WORK(&hso_dev->async_put_intf, async_put_intf);
    INIT_WORK(&hso_dev->reset_device, reset_device);

    return hso_dev;
}

/* Removes a network device in the network device table */
static int remove_net_device(struct hso_device *hso_dev)
{
    int i;

    for (i = 0; i < HSO_MAX_NET_DEVICES; i++) {
        if (network_table[i] == hso_dev) {
            network_table[i] = NULL;
            break;
        }
    }
    if (i == HSO_MAX_NET_DEVICES)
        return -1;
    return 0;
}

/* Frees our network device */
static void hso_free_net_device(struct hso_device *hso_dev)
{
    int i;
    struct hso_net *hso_net = dev2net(hso_dev);

    if (!hso_net)
        return;

    remove_net_device(hso_net->parent);

    if (hso_net->net)
        unregister_netdev(hso_net->net);

    /* start freeing */
    for (i = 0; i < MUX_BULK_RX_BUF_COUNT; i++) {
        usb_free_urb(hso_net->mux_bulk_rx_urb_pool[i]);
        kfree(hso_net->mux_bulk_rx_buf_pool[i]);
        hso_net->mux_bulk_rx_buf_pool[i] = NULL;
    }
    usb_free_urb(hso_net->mux_bulk_tx_urb);
    kfree(hso_net->mux_bulk_tx_buf);
    hso_net->mux_bulk_tx_buf = NULL;

    if (hso_net->net)
        free_netdev(hso_net->net);

    kfree(hso_dev);
}

static const struct net_device_ops hso_netdev_ops = {
    .ndo_open   = hso_net_open,
    .ndo_stop   = hso_net_close,
    .ndo_start_xmit = hso_net_start_xmit,
    .ndo_tx_timeout = hso_net_tx_timeout,
};

/* initialize the network interface */
static void hso_net_init(struct net_device *net)
{
    struct hso_net *hso_net = netdev_priv(net);

    D1("sizeof hso_net is %d", (int)sizeof(*hso_net));

    /* fill in the other fields */
    net->netdev_ops = &hso_netdev_ops;
    net->watchdog_timeo = HSO_NET_TX_TIMEOUT;
    net->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
    net->type = ARPHRD_NONE;
    net->mtu = DEFAULT_MTU - 14;
    net->tx_queue_len = 10;
    SET_ETHTOOL_OPS(net, &ops);

    /* and initialize the semaphore */
    spin_lock_init(&hso_net->net_lock);
}

/* Adds a network device in the network device table */
static int add_net_device(struct hso_device *hso_dev)
{
    int i;

    for (i = 0; i < HSO_MAX_NET_DEVICES; i++) {
        if (network_table[i] == NULL) {
            network_table[i] = hso_dev;
            break;
        }
    }
    if (i == HSO_MAX_NET_DEVICES)
        return -1;
    return 0;
}

static int hso_rfkill_set_block(void *data, bool blocked)
{
    struct hso_device *hso_dev = data;
    int enabled = !blocked;
    int rv;

    mutex_lock(&hso_dev->mutex);
    if (hso_dev->usb_gone)
        rv = 0;
    else
        rv = usb_control_msg(hso_dev->usb, usb_rcvctrlpipe(hso_dev->usb, 0),
                       enabled ? 0x82 : 0x81, 0x40, 0, 0, NULL, 0,
                       USB_CTRL_SET_TIMEOUT);
    mutex_unlock(&hso_dev->mutex);
    return rv;
}

static const struct rfkill_ops hso_rfkill_ops = {
    .set_block = hso_rfkill_set_block,
};

/* Creates and sets up everything for rfkill */
static void hso_create_rfkill(struct hso_device *hso_dev,
                 struct usb_interface *interface)
{
    struct hso_net *hso_net = dev2net(hso_dev);
    struct device *dev = &hso_net->net->dev;
    char *rfkn;

    rfkn = kzalloc(20, GFP_KERNEL);
    if (!rfkn)
        dev_err(dev, "%s - Out of memory\n", __func__);

    snprintf(rfkn, 20, "hso-%d",
         interface->altsetting->desc.bInterfaceNumber);

    hso_net->rfkill = rfkill_alloc(rfkn,
                       &interface_to_usbdev(interface)->dev,
                       RFKILL_TYPE_WWAN,
                       &hso_rfkill_ops, hso_dev);
    if (!hso_net->rfkill) {
        dev_err(dev, "%s - Out of memory\n", __func__);
        kfree(rfkn);
        return;
    }
    if (rfkill_register(hso_net->rfkill) < 0) {
        rfkill_destroy(hso_net->rfkill);
        kfree(rfkn);
        hso_net->rfkill = NULL;
        dev_err(dev, "%s - Failed to register rfkill\n", __func__);
        return;
    }
}

static struct device_type hso_type = {
    .name   = "wwan",
};

/* Creates our network device */
static struct hso_device *hso_create_net_device(struct usb_interface *interface,
                        int port_spec)
{
    int result, i;
    struct net_device *net;
    struct hso_net *hso_net;
    struct hso_device *hso_dev;

    hso_dev = hso_create_device(interface, port_spec);
    if (!hso_dev)
        return NULL;

    /* allocate our network device, then we can put in our private data */
    /* call hso_net_init to do the basic initialization */
    net = alloc_netdev(sizeof(struct hso_net), "hso%d", hso_net_init);
    if (!net) {
        dev_err(&interface->dev, "Unable to create ethernet device\n");
        goto exit;
    }

    hso_net = netdev_priv(net);

    hso_dev->port_data.dev_net = hso_net;
    hso_net->net = net;
    hso_net->parent = hso_dev;

    hso_net->in_endp = hso_get_ep(interface, USB_ENDPOINT_XFER_BULK,
                      USB_DIR_IN);
    if (!hso_net->in_endp) {
        dev_err(&interface->dev, "Can't find BULK IN endpoint\n");
        goto exit;
    }
    hso_net->out_endp = hso_get_ep(interface, USB_ENDPOINT_XFER_BULK,
                       USB_DIR_OUT);
    if (!hso_net->out_endp) {
        dev_err(&interface->dev, "Can't find BULK OUT endpoint\n");
        goto exit;
    }
    SET_NETDEV_DEV(net, &interface->dev);
    SET_NETDEV_DEVTYPE(net, &hso_type);

    /* registering our net device */
    result = register_netdev(net);
    if (result) {
        dev_err(&interface->dev, "Failed to register device\n");
        goto exit;
    }

    /* start allocating */
    for (i = 0; i < MUX_BULK_RX_BUF_COUNT; i++) {
        hso_net->mux_bulk_rx_urb_pool[i] = usb_alloc_urb(0, GFP_KERNEL);
        if (!hso_net->mux_bulk_rx_urb_pool[i]) {
            dev_err(&interface->dev, "Could not allocate rx urb\n");
            goto exit;
        }
        hso_net->mux_bulk_rx_buf_pool[i] = kzalloc(MUX_BULK_RX_BUF_SIZE,
                               GFP_KERNEL);
        if (!hso_net->mux_bulk_rx_buf_pool[i]) {
            dev_err(&interface->dev, "Could not allocate rx buf\n");
            goto exit;
        }
    }
    hso_net->mux_bulk_tx_urb = usb_alloc_urb(0, GFP_KERNEL);
    if (!hso_net->mux_bulk_tx_urb) {
        dev_err(&interface->dev, "Could not allocate tx urb\n");
        goto exit;
    }
    hso_net->mux_bulk_tx_buf = kzalloc(MUX_BULK_TX_BUF_SIZE, GFP_KERNEL);
    if (!hso_net->mux_bulk_tx_buf) {
        dev_err(&interface->dev, "Could not allocate tx buf\n");
        goto exit;
    }

    add_net_device(hso_dev);

    hso_log_port(hso_dev);

    hso_create_rfkill(hso_dev, interface);

    return hso_dev;
exit:
    hso_free_net_device(hso_dev);
    return NULL;
}

static void hso_free_tiomget(struct hso_serial *serial)
{
    struct hso_tiocmget *tiocmget;
    if (!serial)
        return;
    tiocmget = serial->tiocmget;
    if (tiocmget) {
        usb_free_urb(tiocmget->urb);
        tiocmget->urb = NULL;
        serial->tiocmget = NULL;
        kfree(tiocmget);
    }
}

/* Frees an AT channel ( goes for both mux and non-mux ) */
static void hso_free_serial_device(struct hso_device *hso_dev)
{
    struct hso_serial *serial = dev2ser(hso_dev);

    if (!serial)
        return;
    set_serial_by_index(serial->minor, NULL);

    hso_serial_common_free(serial);

    if (serial->shared_int) {
        mutex_lock(&serial->shared_int->shared_int_lock);
        if (--serial->shared_int->ref_count == 0)
            hso_free_shared_int(serial->shared_int);
        else
            mutex_unlock(&serial->shared_int->shared_int_lock);
    }
    hso_free_tiomget(serial);
    kfree(serial);
    kfree(hso_dev);
}

/* Creates a bulk AT channel */
static struct hso_device *hso_create_bulk_serial_device(
            struct usb_interface *interface, int port)
{
    struct hso_device *hso_dev;
    struct hso_serial *serial;
    int num_urbs;
    struct hso_tiocmget *tiocmget;

    hso_dev = hso_create_device(interface, port);
    if (!hso_dev)
        return NULL;

    serial = kzalloc(sizeof(*serial), GFP_KERNEL);
    if (!serial)
        goto exit;

    serial->parent = hso_dev;
    hso_dev->port_data.dev_serial = serial;

    if ((port & HSO_PORT_MASK) == HSO_PORT_MODEM) {
        num_urbs = 2;
        serial->tiocmget = kzalloc(sizeof(struct hso_tiocmget),
                       GFP_KERNEL);
        /* it isn't going to break our heart if serial->tiocmget
         *  allocation fails don't bother checking this.
         */
        if (serial->tiocmget) {
            tiocmget = serial->tiocmget;
            tiocmget->urb = usb_alloc_urb(0, GFP_KERNEL);
            if (tiocmget->urb) {
                mutex_init(&tiocmget->mutex);
                init_waitqueue_head(&tiocmget->waitq);
                tiocmget->endp = hso_get_ep(
                    interface,
                    USB_ENDPOINT_XFER_INT,
                    USB_DIR_IN);
            } else
                hso_free_tiomget(serial);
        }
    }
    else
        num_urbs = 1;

    if (hso_serial_common_create(serial, num_urbs, BULK_URB_RX_SIZE,
                     BULK_URB_TX_SIZE))
        goto exit;

    serial->in_endp = hso_get_ep(interface, USB_ENDPOINT_XFER_BULK,
                     USB_DIR_IN);
    if (!serial->in_endp) {
        dev_err(&interface->dev, "Failed to find BULK IN ep\n");
        goto exit2;
    }

    if (!
        (serial->out_endp =
         hso_get_ep(interface, USB_ENDPOINT_XFER_BULK, USB_DIR_OUT))) {
        dev_err(&interface->dev, "Failed to find BULK IN ep\n");
        goto exit2;
    }

    serial->write_data = hso_std_serial_write_data;

    /* and record this serial */
    set_serial_by_index(serial->minor, serial);

    /* setup the proc dirs and files if needed */
    hso_log_port(hso_dev);

    /* done, return it */
    return hso_dev;

exit2:
    hso_serial_common_free(serial);
exit:
    hso_free_tiomget(serial);
    kfree(serial);
    kfree(hso_dev);
    return NULL;
}

/* Creates a multiplexed AT channel */
static
struct hso_device *hso_create_mux_serial_device(struct usb_interface *interface,
                        int port,
                        struct hso_shared_int *mux)
{
    struct hso_device *hso_dev;
    struct hso_serial *serial;
    int port_spec;

    port_spec = HSO_INTF_MUX;
    port_spec &= ~HSO_PORT_MASK;

    port_spec |= hso_mux_to_port(port);
    if ((port_spec & HSO_PORT_MASK) == HSO_PORT_NO_PORT)
        return NULL;

    hso_dev = hso_create_device(interface, port_spec);
    if (!hso_dev)
        return NULL;

    serial = kzalloc(sizeof(*serial), GFP_KERNEL);
    if (!serial)
        goto exit;

    hso_dev->port_data.dev_serial = serial;
    serial->parent = hso_dev;

    if (hso_serial_common_create
        (serial, 1, CTRL_URB_RX_SIZE, CTRL_URB_TX_SIZE))
        goto exit;

    serial->tx_data_length--;
    serial->write_data = hso_mux_serial_write_data;

    serial->shared_int = mux;
    mutex_lock(&serial->shared_int->shared_int_lock);
    serial->shared_int->ref_count++;
    mutex_unlock(&serial->shared_int->shared_int_lock);

    /* and record this serial */
    set_serial_by_index(serial->minor, serial);

    /* setup the proc dirs and files if needed */
    hso_log_port(hso_dev);

    /* done, return it */
    return hso_dev;

exit:
    if (serial) {
        tty_unregister_device(tty_drv, serial->minor);
        kfree(serial);
    }
    if (hso_dev)
        kfree(hso_dev);
    return NULL;

}

static void hso_free_shared_int(struct hso_shared_int *mux)
{
    usb_free_urb(mux->shared_intr_urb);
    kfree(mux->shared_intr_buf);
    mutex_unlock(&mux->shared_int_lock);
    kfree(mux);
}

static
struct hso_shared_int *hso_create_shared_int(struct usb_interface *interface)
{
    struct hso_shared_int *mux = kzalloc(sizeof(*mux), GFP_KERNEL);

    if (!mux)
        return NULL;

    mux->intr_endp = hso_get_ep(interface, USB_ENDPOINT_XFER_INT,
                    USB_DIR_IN);
    if (!mux->intr_endp) {
        dev_err(&interface->dev, "Can't find INT IN endpoint\n");
        goto exit;
    }

    mux->shared_intr_urb = usb_alloc_urb(0, GFP_KERNEL);
    if (!mux->shared_intr_urb) {
        dev_err(&interface->dev, "Could not allocate intr urb?\n");
        goto exit;
    }
    mux->shared_intr_buf =
        kzalloc(le16_to_cpu(mux->intr_endp->wMaxPacketSize),
            GFP_KERNEL);
    if (!mux->shared_intr_buf) {
        dev_err(&interface->dev, "Could not allocate intr buf?\n");
        goto exit;
    }

    mutex_init(&mux->shared_int_lock);

    return mux;

exit:
    kfree(mux->shared_intr_buf);
    usb_free_urb(mux->shared_intr_urb);
    kfree(mux);
    return NULL;
}

/* Gets the port spec for a certain interface */
static int hso_get_config_data(struct usb_interface *interface)
{
    struct usb_device *usbdev = interface_to_usbdev(interface);
    u8 config_data[17];
    u32 if_num = interface->altsetting->desc.bInterfaceNumber;
    s32 result;

    if (usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0),
                0x86, 0xC0, 0, 0, config_data, 17,
                USB_CTRL_SET_TIMEOUT) != 0x11) {
        return -EIO;
    }

    switch (config_data[if_num]) {
    case 0x0:
        result = 0;
        break;
    case 0x1:
        result = HSO_PORT_DIAG;
        break;
    case 0x2:
        result = HSO_PORT_GPS;
        break;
    case 0x3:
        result = HSO_PORT_GPS_CONTROL;
        break;
    case 0x4:
        result = HSO_PORT_APP;
        break;
    case 0x5:
        result = HSO_PORT_APP2;
        break;
    case 0x6:
        result = HSO_PORT_CONTROL;
        break;
    case 0x7:
        result = HSO_PORT_NETWORK;
        break;
    case 0x8:
        result = HSO_PORT_MODEM;
        break;
    case 0x9:
        result = HSO_PORT_MSD;
        break;
    case 0xa:
        result = HSO_PORT_PCSC;
        break;
    case 0xb:
        result = HSO_PORT_VOICE;
        break;
    default:
        result = 0;
    }

    if (result)
        result |= HSO_INTF_BULK;

    if (config_data[16] & 0x1)
        result |= HSO_INFO_CRC_BUG;

    return result;
}

/* called once for each interface upon device insertion */
static int hso_probe(struct usb_interface *interface,
             const struct usb_device_id *id)
{
    int mux, i, if_num, port_spec;
    unsigned char port_mask;
    struct hso_device *hso_dev = NULL;
    struct hso_shared_int *shared_int;
    struct hso_device *tmp_dev = NULL;

    if_num = interface->altsetting->desc.bInterfaceNumber;

    /* Get the interface/port specification from either driver_info or from
     * the device itself */
    if (id->driver_info)
        port_spec = ((u32 *)(id->driver_info))[if_num];
    else
        port_spec = hso_get_config_data(interface);

    if (interface->cur_altsetting->desc.bInterfaceClass != 0xFF) {
        dev_err(&interface->dev, "Not our interface\n");
        return -ENODEV;
    }
    /* Check if we need to switch to alt interfaces prior to port
     * configuration */
    if (interface->num_altsetting > 1)
        usb_set_interface(interface_to_usbdev(interface), if_num, 1);
    interface->needs_remote_wakeup = 1;

    /* Allocate new hso device(s) */
    switch (port_spec & HSO_INTF_MASK) {
    case HSO_INTF_MUX:
        if ((port_spec & HSO_PORT_MASK) == HSO_PORT_NETWORK) {
            /* Create the network device */
            if (!disable_net) {
                hso_dev = hso_create_net_device(interface,
                                port_spec);
                if (!hso_dev)
                    goto exit;
                tmp_dev = hso_dev;
            }
        }

        if (hso_get_mux_ports(interface, &port_mask))
            /* TODO: de-allocate everything */
            goto exit;

        shared_int = hso_create_shared_int(interface);
        if (!shared_int)
            goto exit;

        for (i = 1, mux = 0; i < 0x100; i = i << 1, mux++) {
            if (port_mask & i) {
                hso_dev = hso_create_mux_serial_device(
                        interface, i, shared_int);
                if (!hso_dev)
                    goto exit;
            }
        }

        if (tmp_dev)
            hso_dev = tmp_dev;
        break;

    case HSO_INTF_BULK:
        /* It's a regular bulk interface */
        if ((port_spec & HSO_PORT_MASK) == HSO_PORT_NETWORK) {
            if (!disable_net)
                hso_dev =
                    hso_create_net_device(interface, port_spec);
        } else {
            hso_dev =
                hso_create_bulk_serial_device(interface, port_spec);
        }
        if (!hso_dev)
            goto exit;
        break;
    default:
        goto exit;
    }

    /* save our data pointer in this device */
    usb_set_intfdata(interface, hso_dev);

    /* done */
    return 0;
exit:
    hso_free_interface(interface);
    return -ENODEV;
}

/* device removed, cleaning up */
static void hso_disconnect(struct usb_interface *interface)
{
    hso_free_interface(interface);

    /* remove reference of our private data */
    usb_set_intfdata(interface, NULL);
}

static void async_get_intf(struct work_struct *data)
{
    struct hso_device *hso_dev =
        container_of(data, struct hso_device, async_get_intf);
    usb_autopm_get_interface(hso_dev->interface);
}

static void async_put_intf(struct work_struct *data)
{
    struct hso_device *hso_dev =
        container_of(data, struct hso_device, async_put_intf);
    usb_autopm_put_interface(hso_dev->interface);
}

static int hso_get_activity(struct hso_device *hso_dev)
{
    if (hso_dev->usb->state == USB_STATE_SUSPENDED) {
        if (!hso_dev->is_active) {
            hso_dev->is_active = 1;
            schedule_work(&hso_dev->async_get_intf);
        }
    }

    if (hso_dev->usb->state != USB_STATE_CONFIGURED)
        return -EAGAIN;

    usb_mark_last_busy(hso_dev->usb);

    return 0;
}

static int hso_put_activity(struct hso_device *hso_dev)
{
    if (hso_dev->usb->state != USB_STATE_SUSPENDED) {
        if (hso_dev->is_active) {
            hso_dev->is_active = 0;
            schedule_work(&hso_dev->async_put_intf);
            return -EAGAIN;
        }
    }
    hso_dev->is_active = 0;
    return 0;
}

/* called by kernel when we need to suspend device */
static int hso_suspend(struct usb_interface *iface, pm_message_t message)
{
    int i, result;

    /* Stop all serial ports */
    for (i = 0; i < HSO_SERIAL_TTY_MINORS; i++) {
        if (serial_table[i] && (serial_table[i]->interface == iface)) {
            result = hso_stop_serial_device(serial_table[i]);
            if (result)
                goto out;
        }
    }

    /* Stop all network ports */
    for (i = 0; i < HSO_MAX_NET_DEVICES; i++) {
        if (network_table[i] &&
            (network_table[i]->interface == iface)) {
            result = hso_stop_net_device(network_table[i]);
            if (result)
                goto out;
        }
    }

out:
    return 0;
}

/* called by kernel when we need to resume device */
static int hso_resume(struct usb_interface *iface)
{
    int i, result = 0;
    struct hso_net *hso_net;

    /* Start all serial ports */
    for (i = 0; i < HSO_SERIAL_TTY_MINORS; i++) {
        if (serial_table[i] && (serial_table[i]->interface == iface)) {
            if (dev2ser(serial_table[i])->port.count) {
                result =
                    hso_start_serial_device(serial_table[i], GFP_NOIO);
                hso_kick_transmit(dev2ser(serial_table[i]));
                if (result)
                    goto out;
            }
        }
    }

    /* Start all network ports */
    for (i = 0; i < HSO_MAX_NET_DEVICES; i++) {
        if (network_table[i] &&
            (network_table[i]->interface == iface)) {
            hso_net = dev2net(network_table[i]);
            if (hso_net->flags & IFF_UP) {
                /* First transmit any lingering data,
                   then restart the device. */
                if (hso_net->skb_tx_buf) {
                    dev_dbg(&iface->dev,
                        "Transmitting"
                        " lingering data\n");
                    hso_net_start_xmit(hso_net->skb_tx_buf,
                               hso_net->net);
                    hso_net->skb_tx_buf = NULL;
                }
                result = hso_start_net_device(network_table[i]);
                if (result)
                    goto out;
            }
        }
    }

out:
    return result;
}

static void reset_device(struct work_struct *data)
{
    struct hso_device *hso_dev =
        container_of(data, struct hso_device, reset_device);
    struct usb_device *usb = hso_dev->usb;
    int result;

    if (hso_dev->usb_gone) {
        D1("No reset during disconnect\n");
    } else {
        result = usb_lock_device_for_reset(usb, hso_dev->interface);
        if (result < 0)
            D1("unable to lock device for reset: %d\n", result);
        else {
            usb_reset_device(usb);
            usb_unlock_device(usb);
        }
    }
}

static void hso_serial_ref_free(struct kref *ref)
{
    struct hso_device *hso_dev = container_of(ref, struct hso_device, ref);

    hso_free_serial_device(hso_dev);
}

static void hso_free_interface(struct usb_interface *interface)
{
    struct hso_serial *hso_dev;
    struct tty_struct *tty;
    int i;

    for (i = 0; i < HSO_SERIAL_TTY_MINORS; i++) {
        if (serial_table[i] &&
            (serial_table[i]->interface == interface)) {
            hso_dev = dev2ser(serial_table[i]);
            tty = tty_port_tty_get(&hso_dev->port);
            if (tty) {
                tty_hangup(tty);
                tty_kref_put(tty);
            }
            mutex_lock(&hso_dev->parent->mutex);
            hso_dev->parent->usb_gone = 1;
            mutex_unlock(&hso_dev->parent->mutex);
            kref_put(&serial_table[i]->ref, hso_serial_ref_free);
        }
    }

    for (i = 0; i < HSO_MAX_NET_DEVICES; i++) {
        if (network_table[i] &&
            (network_table[i]->interface == interface)) {
            struct rfkill *rfk = dev2net(network_table[i])->rfkill;
            /* hso_stop_net_device doesn't stop the net queue since
             * traffic needs to start it again when suspended */
            netif_stop_queue(dev2net(network_table[i])->net);
            hso_stop_net_device(network_table[i]);
            cancel_work_sync(&network_table[i]->async_put_intf);
            cancel_work_sync(&network_table[i]->async_get_intf);
            if (rfk) {
                rfkill_unregister(rfk);
                rfkill_destroy(rfk);
            }
            hso_free_net_device(network_table[i]);
        }
    }
}

/* Helper functions */

/* Get the endpoint ! */
static struct usb_endpoint_descriptor *hso_get_ep(struct usb_interface *intf,
                          int type, int dir)
{
    int i;
    struct usb_host_interface *iface = intf->cur_altsetting;
    struct usb_endpoint_descriptor *endp;

    for (i = 0; i < iface->desc.bNumEndpoints; i++) {
        endp = &iface->endpoint[i].desc;
        if (((endp->bEndpointAddress & USB_ENDPOINT_DIR_MASK) == dir) &&
            (usb_endpoint_type(endp) == type))
            return endp;
    }

    return NULL;
}

/* Get the byte that describes which ports are enabled */
static int hso_get_mux_ports(struct usb_interface *intf, unsigned char *ports)
{
    int i;
    struct usb_host_interface *iface = intf->cur_altsetting;

    if (iface->extralen == 3) {
        *ports = iface->extra[2];
        return 0;
    }

    for (i = 0; i < iface->desc.bNumEndpoints; i++) {
        if (iface->endpoint[i].extralen == 3) {
            *ports = iface->endpoint[i].extra[2];
            return 0;
        }
    }

    return -1;
}

/* interrupt urb needs to be submitted, used for serial read of muxed port */
static int hso_mux_submit_intr_urb(struct hso_shared_int *shared_int,
                   struct usb_device *usb, gfp_t gfp)
{
    int result;

    usb_fill_int_urb(shared_int->shared_intr_urb, usb,
             usb_rcvintpipe(usb,
                shared_int->intr_endp->bEndpointAddress & 0x7F),
             shared_int->shared_intr_buf,
             1,
             intr_callback, shared_int,
             shared_int->intr_endp->bInterval);

    result = usb_submit_urb(shared_int->shared_intr_urb, gfp);
    if (result)
        dev_warn(&usb->dev, "%s failed mux_intr_urb %d\n", __func__,
            result);

    return result;
}

/* operations setup of the serial interface */
static const struct tty_operations hso_serial_ops = {
    .open = hso_serial_open,
    .close = hso_serial_close,
    .write = hso_serial_write,
    .write_room = hso_serial_write_room,
    .ioctl = hso_serial_ioctl,
    .set_termios = hso_serial_set_termios,
    .chars_in_buffer = hso_serial_chars_in_buffer,
    .tiocmget = hso_serial_tiocmget,
    .tiocmset = hso_serial_tiocmset,
    .get_icount = hso_get_count,
    .unthrottle = hso_unthrottle
};

static struct usb_driver hso_driver = {
    .name = driver_name,
    .probe = hso_probe,
    .disconnect = hso_disconnect,
    .id_table = hso_ids,
    .suspend = hso_suspend,
    .resume = hso_resume,
    .reset_resume = hso_resume,
    .supports_autosuspend = 1,
    .disable_hub_initiated_lpm = 1,
};

static int __init hso_init(void)
{
    int i;
    int result;

    /* put it in the log */
    printk(KERN_INFO "hso: %s\n", version);

    /* Initialise the serial table semaphore and table */
    spin_lock_init(&serial_table_lock);
    for (i = 0; i < HSO_SERIAL_TTY_MINORS; i++)
        serial_table[i] = NULL;

    /* allocate our driver using the proper amount of supported minors */
    tty_drv = alloc_tty_driver(HSO_SERIAL_TTY_MINORS);
    if (!tty_drv)
        return -ENOMEM;

    /* fill in all needed values */
    tty_drv->driver_name = driver_name;
    tty_drv->name = tty_filename;

    /* if major number is provided as parameter, use that one */
    if (tty_major)
        tty_drv->major = tty_major;

    tty_drv->minor_start = 0;
    tty_drv->type = TTY_DRIVER_TYPE_SERIAL;
    tty_drv->subtype = SERIAL_TYPE_NORMAL;
    tty_drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
    tty_drv->init_termios = tty_std_termios;
    hso_init_termios(&tty_drv->init_termios);
    tty_set_operations(tty_drv, &hso_serial_ops);

    /* register the tty driver */
    result = tty_register_driver(tty_drv);
    if (result) {
        printk(KERN_ERR "%s - tty_register_driver failed(%d)\n",
            __func__, result);
        goto err_free_tty;
    }

    /* register this module as an usb driver */
    result = usb_register(&hso_driver);
    if (result) {
        printk(KERN_ERR "Could not register hso driver? error: %d\n",
            result);
        goto err_unreg_tty;
    }

    /* done */
    return 0;
err_unreg_tty:
    tty_unregister_driver(tty_drv);
err_free_tty:
    put_tty_driver(tty_drv);
    return result;
}

static void __exit hso_exit(void)
{
    printk(KERN_INFO "hso: unloaded\n");

    tty_unregister_driver(tty_drv);
    put_tty_driver(tty_drv);
    /* deregister the usb driver */
    usb_deregister(&hso_driver);
}

/* Module definitions */
module_init(hso_init);
module_exit(hso_exit);

MODULE_AUTHOR(MOD_AUTHOR);
MODULE_DESCRIPTION(MOD_DESCRIPTION);
MODULE_LICENSE(MOD_LICENSE);

/* change the debug level (eg: insmod hso.ko debug=0x04) */
MODULE_PARM_DESC(debug, "Level of debug [0x01 | 0x02 | 0x04 | 0x08 | 0x10]");
module_param(debug, int, S_IRUGO | S_IWUSR);

/* set the major tty number (eg: insmod hso.ko tty_major=245) */
MODULE_PARM_DESC(tty_major, "Set the major tty number");
module_param(tty_major, int, S_IRUGO | S_IWUSR);

/* disable network interface (eg: insmod hso.ko disable_net=1) */
MODULE_PARM_DESC(disable_net, "Disable the network interface");
module_param(disable_net, int, S_IRUGO | S_IWUSR);