drivers/net/usb/hso.c

root/drivers/net/usb/hso.c
// SPDX-License-Identifier: GPL-2.0-only
/******************************************************************************
 *
 * Driver for Option High Speed Mobile Devices.
 *
 *  Copyright (C) 2008 Option International
 *                     Filip Aben <f.aben@option.com>
 *                     Denis Joseph Barrow <d.barow@option.com>
 *                     Jan Dumon <j.dumon@option.com>
 *  Copyright (C) 2007 Andrew Bird (Sphere Systems Ltd)
 *                      <ajb@spheresystems.co.uk>
 *  Copyright (C) 2008 Greg Kroah-Hartman <gregkh@suse.de>
 *  Copyright (C) 2008 Novell, Inc.
 *
 *****************************************************************************/

/******************************************************************************
 *
 * 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.
 *
 *****************************************************************************/

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/sched/signal.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/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 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 hso_dbg(lvl, fmt, ...)                                          \
do {                                                                    \
        if ((lvl) & debug)                                              \
                pr_info("[%d:%s] " fmt,                                 \
                        __LINE__, __func__, ##__VA_ARGS__);             \
} while (0)

/*****************************************************************************/
/* 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;
        char name[24];

        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_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;
        u8   rx_urb_filled[MAX_RX_URBS];
        struct tasklet_struct unthrottle_tasklet;
};

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 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);
/*****************************************************************************/
/* 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";
/* 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 DEFINE_SPINLOCK(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, 0x9200)},           /* Option GTM671WFS */
        {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 hsotype_show(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_RO(hsotype);

static struct attribute *hso_serial_dev_attrs[] = {
        &dev_attr_hsotype.attr,
        NULL
};

ATTRIBUTE_GROUPS(hso_serial_dev);

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 obtain_minor(struct hso_serial *serial)
{
        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) {
                        serial_table[index] = serial->parent;
                        serial->minor = index;
                        spin_unlock_irqrestore(&serial_table_lock, flags);
                        return 0;
                }
        }
        spin_unlock_irqrestore(&serial_table_lock, flags);

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

static void release_minor(struct hso_serial *serial)
{
        unsigned long flags;

        spin_lock_irqsave(&serial_table_lock, flags);
        serial_table[serial->minor] = 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)
                        usb_queue_reset_device(hso_dev->interface);
                break;
        default:
                explanation = "unknown status";
                break;
        }

        /* log a meaningful explanation of an USB status */
        hso_dbg(0x1, "%s: received USB status - %s (%d)\n",
                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);
        hso_dbg(0x1, "len: %d/%d\n", 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, unsigned int txqueue)
{
        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)
                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;

        /* log if needed */
        hso_dbg(0x1, "Rx %d bytes\n", 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. */
                                        hso_dbg(0x1, "could not allocate memory\n");
                                        odev->rx_parse_state = WAIT_SYNC;
                                        continue;
                                }

                                /* Copy what we got so far. make room for iphdr
                                 * after tail. */
                                skb_put_data(odev->skb_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. */
                        skb_put_data(odev->skb_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:
                        hso_dbg(0x1, " W_S\n");
                        count = 0;
                        break;
                default:
                        hso_dbg(0x1, "\n");
                        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;
        unsigned long flags;
        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)) {
                hso_dbg(0x1, "BULK IN callback but driver is not active!\n");
                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_irqsave(&odev->net_lock, flags);
                packetizeRx(odev, urb->transfer_buffer, urb->actual_length,
                            (urb->transfer_buffer_length >
                             urb->actual_length) ? 1 : 0);
                spin_unlock_irqrestore(&odev->net_lock, flags);
        }

        /* 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 hso_serial *serial = tty->driver_data;

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

        hso_dbg(0x8, "port %d\n", 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;
        unsigned long flags;

        hso_dbg(0x8, "--- Got serial_read_bulk callback %02x ---\n", status);

        /* sanity check */
        if (!serial) {
                hso_dbg(0x1, "serial == NULL\n");
                return;
        }
        if (status) {
                handle_usb_error(status, __func__, serial->parent);
                return;
        }

        hso_dbg(0x1, "Actual length = %d\n", urb->actual_length);
        DUMP1(urb->transfer_buffer, urb->actual_length);

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

        if (serial->parent->port_spec & HSO_INFO_CRC_BUG)
                fix_crc_bug(urb, serial->in_endp->wMaxPacketSize);
        /* Valid data, handle RX data */
        spin_lock_irqsave(&serial->serial_lock, flags);
        serial->rx_urb_filled[hso_urb_to_index(serial, urb)] = 1;
        put_rxbuf_data_and_resubmit_bulk_urb(serial);
        spin_unlock_irqrestore(&serial->serial_lock, flags);
}

/*
 * This needs to be a tasklet otherwise we will
 * end up recursively calling this function.
 */
static void hso_unthrottle_tasklet(struct tasklet_struct *t)
{
        struct hso_serial *serial = from_tasklet(serial, t,
                                                 unthrottle_tasklet);
        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);
}

/* 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;
                hso_dbg(0x1, "Failed to open port\n");
                return -ENODEV;
        }

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

        hso_dbg(0x1, "Opening %d\n", serial->minor);

        /* 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);
                tasklet_setup(&serial->unthrottle_tasklet,
                              hso_unthrottle_tasklet);
                result = hso_start_serial_device(serial->parent, GFP_KERNEL);
                if (result) {
                        hso_stop_serial_device(serial->parent);
                        serial->port.count--;
                } else {
                        kref_get(&serial->parent->ref);
                }
        } else {
                hso_dbg(0x1, "Port was already open\n");
        }

        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;

        hso_dbg(0x1, "Closing serial port\n");

        /* 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);
        }

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

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

/* close the requested serial port */
static ssize_t hso_serial_write(struct tty_struct *tty, const u8 *buf,
                                size_t count)
{
        struct hso_serial *serial = tty->driver_data;
        unsigned long flags;

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

        spin_lock_irqsave(&serial->serial_lock, flags);

        count = min_t(size_t, serial->tx_data_length - serial->tx_buffer_count,
                      count);
        memcpy(serial->tx_buffer + serial->tx_buffer_count, buf, count);
        serial->tx_buffer_count += count;

        spin_unlock_irqrestore(&serial->serial_lock, flags);

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

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

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

        if (!serial)
                return;

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

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

        if (old)
                hso_dbg(0x16, "Termios called with: cflags new[%u] - old[%u]\n",
                        (unsigned int)tty->termios.c_cflag,
                        (unsigned int)old->c_cflag);

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

        /* done */
}

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

        /* 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;
        struct usb_interface *interface;
        int if_num;

        /* Sanity checks */
        if (!serial)
                return;
        if (status) {
                handle_usb_error(status, __func__, serial->parent);
                return;
        }

        /* tiocmget is only supported on HSO_PORT_MODEM */
        tiocmget = serial->tiocmget;
        if (!tiocmget)
                return;
        BUG_ON((serial->parent->port_spec & HSO_PORT_MASK) != HSO_PORT_MODEM);

        usb = serial->parent->usb;
        interface = serial->parent->interface;

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

        /* wIndex should be the USB interface number of the port to which the
         * notification applies, which should always be the Modem port.
         */
        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) != if_num ||
            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 {
                unsigned long flags;

                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_irqsave(&serial->serial_lock, flags);
                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_irqrestore(&serial->serial_lock, flags);
                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;
        }
        __set_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) {
                hso_dbg(0x1, "no tty structures\n");
                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;
        struct usb_interface *interface;

        /* sanity check */
        if (!serial) {
                hso_dbg(0x1, "no tty structures\n");
                return -EINVAL;
        }

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

        interface = serial->parent->interface;
        if_num = interface->cur_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_sndctrlpipe(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;
        hso_dbg(0x8, "IOCTL cmd: %d, arg: %ld\n", 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)
{
        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 */
        swap(serial->tx_buffer, serial->tx_data);
        serial->tx_data_count = serial->tx_buffer_count;
        serial->tx_buffer_count = 0;

        /* If serial->tx_data is set, it means we switched buffers */
        if (serial->tx_data && 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) {
                pr_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 */
        hso_dbg(0x2, "%s command (%02x) len: %d, port: %d\n",
                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;
        unsigned long flags;
        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;
        }
        hso_dbg(0x8, "--- Got intr callback 0x%02X ---\n", status);

        /* what request? */
        port_req = urb->transfer_buffer;
        hso_dbg(0x8, "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) {
                                hso_dbg(0x1, "Pending read interrupt on port %d\n",
                                        i);
                                spin_lock_irqsave(&serial->serial_lock, flags);
                                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 {
                                        hso_dbg(0x1, "Already a read pending on port %d or port not open\n",
                                                i);
                                }
                                spin_unlock_irqrestore(&serial->serial_lock,
                                                       flags);
                        }
                }
        }
        /* 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;
        unsigned long flags;

        /* sanity check */
        if (!serial) {
                hso_dbg(0x1, "serial == NULL\n");
                return;
        }

        spin_lock_irqsave(&serial->serial_lock, flags);
        serial->tx_urb_used = 0;
        spin_unlock_irqrestore(&serial->serial_lock, flags);
        if (status) {
                handle_usb_error(status, __func__, serial->parent);
                return;
        }
        hso_put_activity(serial->parent);
        tty_port_tty_wakeup(&serial->port);
        hso_kick_transmit(serial);

        hso_dbg(0x1, "\n");
}

/* 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;
        unsigned long flags;

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

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

        /* what request? */
        req = (struct usb_ctrlrequest *)(urb->setup_packet);
        hso_dbg(0x8, "--- Got muxed ctrl callback 0x%02X ---\n", status);
        hso_dbg(0x8, "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_irqsave(&serial->serial_lock, flags);
                put_rxbuf_data_and_resubmit_ctrl_urb(serial);
                spin_unlock_irqrestore(&serial->serial_lock, flags);
        } else {
                hso_put_activity(serial->parent);
                tty_port_tty_wakeup(&serial->port);
                /* 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 count;

        /* Sanity check */
        if (urb == NULL || serial == NULL) {
                hso_dbg(0x1, "serial = NULL\n");
                return -2;
        }

        tty = tty_port_tty_get(&serial->port);

        if (tty && tty_throttled(tty)) {
                tty_kref_put(tty);
                return -1;
        }

        /* Push data to tty */
        hso_dbg(0x1, "data to push to tty\n");
        count = tty_buffer_request_room(&serial->port, urb->actual_length);
        if (count >= urb->actual_length) {
                tty_insert_flip_string(&serial->port, urb->transfer_buffer,
                                       urb->actual_length);
                tty_flip_buffer_push(&serial->port);
        } else {
                dev_warn(&serial->parent->usb->dev,
                         "dropping data, %d bytes lost\n", urb->actual_length);
        }

        tty_kref_put(tty);

        serial->rx_urb_filled[hso_urb_to_index(serial, urb)] = 0;

        return 0;
}


/* 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;

        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_tty_unregister(struct hso_serial *serial)
{
        tty_unregister_device(tty_drv, serial->minor);
        release_minor(serial);
}

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

        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_buffer);
        kfree(serial->tx_data);
        tty_port_destroy(&serial->port);
}

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

        tty_port_init(&serial->port);

        if (obtain_minor(serial))
                goto exit2;

        /* register our minor number */
        serial->parent->dev = tty_port_register_device_attr(&serial->port,
                        tty_drv, serial->minor, &serial->parent->interface->dev,
                        serial->parent, hso_serial_dev_groups);
        if (IS_ERR(serial->parent->dev)) {
                release_minor(serial);
                goto exit2;
        }

        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])
                        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])
                        goto exit;
        }

        /* TX, allocate urb and initialize */
        serial->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!serial->tx_urb)
                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)
                goto exit;

        serial->tx_buffer = kzalloc(serial->tx_data_length, GFP_KERNEL);
        if (!serial->tx_buffer)
                goto exit;

        return 0;
exit:
        hso_serial_tty_unregister(serial);
exit2:
        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_obj(*hso_dev);
        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);

        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);

        hso_dbg(0x1, "sizeof hso_net is %zu\n", 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;
        net->ethtool_ops = &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_sndctrlpipe(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;
        static u32 rfkill_counter;

        snprintf(hso_net->name, sizeof(hso_net->name), "hso-%d",
                 rfkill_counter++);

        hso_net->rfkill = rfkill_alloc(hso_net->name,
                                       &interface_to_usbdev(interface)->dev,
                                       RFKILL_TYPE_WWAN,
                                       &hso_rfkill_ops, hso_dev);
        if (!hso_net->rfkill)
                return;

        if (rfkill_register(hso_net->rfkill) < 0) {
                rfkill_destroy(hso_net->rfkill);
                hso_net->rfkill = NULL;
                dev_err(dev, "%s - Failed to register rfkill\n", __func__);
                return;
        }
}

static const 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", NET_NAME_UNKNOWN,
                           hso_net_init);
        if (!net) {
                dev_err(&interface->dev, "Unable to create ethernet device\n");
                goto err_hso_dev;
        }

        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 err_net;
        }
        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 err_net;
        }
        SET_NETDEV_DEV(net, &interface->dev);
        SET_NETDEV_DEVTYPE(net, &hso_type);

        /* 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])
                        goto err_mux_bulk_rx;
                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])
                        goto err_mux_bulk_rx;
        }
        hso_net->mux_bulk_tx_urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!hso_net->mux_bulk_tx_urb)
                goto err_mux_bulk_rx;
        hso_net->mux_bulk_tx_buf = kzalloc(MUX_BULK_TX_BUF_SIZE, GFP_KERNEL);
        if (!hso_net->mux_bulk_tx_buf)
                goto err_free_tx_urb;

        result = add_net_device(hso_dev);
        if (result) {
                dev_err(&interface->dev, "Failed to add net device\n");
                goto err_free_tx_buf;
        }

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

        hso_log_port(hso_dev);

        hso_create_rfkill(hso_dev, interface);

        return hso_dev;

err_rmv_ndev:
        remove_net_device(hso_dev);
err_free_tx_buf:
        kfree(hso_net->mux_bulk_tx_buf);
err_free_tx_urb:
        usb_free_urb(hso_net->mux_bulk_tx_urb);
err_mux_bulk_rx:
        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]);
        }
err_net:
        free_netdev(net);
err_hso_dev:
        kfree(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->serial_state_notification);
                tiocmget->serial_state_notification = 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;

        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_obj(*serial);
        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_obj(struct hso_tiocmget);
                if (!serial->tiocmget)
                        goto exit;
                serial->tiocmget->serial_state_notification
                        = kzalloc_obj(struct hso_serial_state_notification);
                if (!serial->tiocmget->serial_state_notification)
                        goto exit;
                tiocmget = serial->tiocmget;
                tiocmget->endp = hso_get_ep(interface,
                                            USB_ENDPOINT_XFER_INT,
                                            USB_DIR_IN);
                if (!tiocmget->endp) {
                        dev_err(&interface->dev, "Failed to find INT IN ep\n");
                        goto exit;
                }

                tiocmget->urb = usb_alloc_urb(0, GFP_KERNEL);
                if (!tiocmget->urb)
                        goto exit;

                mutex_init(&tiocmget->mutex);
                init_waitqueue_head(&tiocmget->waitq);
        } 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 OUT ep\n");
                goto exit2;
        }

        serial->write_data = hso_std_serial_write_data;

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

        /* done, return it */
        return hso_dev;

exit2:
        hso_serial_tty_unregister(serial);
        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_obj(*serial);
        if (!serial)
                goto err_free_dev;

        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 err_free_serial;

        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);

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

        /* done, return it */
        return hso_dev;

err_free_serial:
        kfree(serial);
err_free_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_obj(*mux);

        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)
                goto exit;
        mux->shared_intr_buf =
                kzalloc(le16_to_cpu(mux->intr_endp->wMaxPacketSize),
                        GFP_KERNEL);
        if (!mux->shared_intr_buf)
                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 = kmalloc(17, GFP_KERNEL);
        u32 if_num = interface->cur_altsetting->desc.bInterfaceNumber;
        s32 result;

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

        /* check if we have a valid interface */
        if (if_num > 16) {
                kfree(config_data);
                return -EINVAL;
        }

        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;

        kfree(config_data);
        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 (interface->cur_altsetting->desc.bInterfaceClass != 0xFF) {
                dev_err(&interface->dev, "Not our interface\n");
                return -ENODEV;
        }

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

        /* Get the interface/port specification from either driver_info or from
         * the device itself */
        if (id->driver_info) {
                /* if_num is controlled by the device, driver_info is a 0 terminated
                 * array. Make sure, the access is in bounds! */
                for (i = 0; i <= if_num; ++i)
                        if (((u32 *)(id->driver_info))[i] == 0)
                                goto exit;
                port_spec = ((u32 *)(id->driver_info))[if_num];
        } else {
                port_spec = hso_get_config_data(interface);
                if (port_spec < 0)
                        goto exit;
        }

        /* 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 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 *serial;
        int i;

        for (i = 0; i < HSO_SERIAL_TTY_MINORS; i++) {
                if (serial_table[i] &&
                    (serial_table[i]->interface == interface)) {
                        serial = dev2ser(serial_table[i]);
                        tty_port_tty_hangup(&serial->port, false);
                        mutex_lock(&serial->parent->mutex);
                        serial->parent->usb_gone = 1;
                        mutex_unlock(&serial->parent->mutex);
                        cancel_work_sync(&serial_table[i]->async_put_intf);
                        cancel_work_sync(&serial_table[i]->async_get_intf);
                        hso_serial_tty_unregister(serial);
                        kref_put(&serial->parent->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,
        .cleanup = hso_serial_cleanup,
        .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 result;

        /* allocate our driver using the proper amount of supported minors */
        tty_drv = tty_alloc_driver(HSO_SERIAL_TTY_MINORS, TTY_DRIVER_REAL_RAW |
                        TTY_DRIVER_DYNAMIC_DEV);
        if (IS_ERR(tty_drv))
                return PTR_ERR(tty_drv);

        /* 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->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) {
                pr_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) {
                pr_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:
        tty_driver_kref_put(tty_drv);
        return result;
}

static void __exit hso_exit(void)
{
        tty_unregister_driver(tty_drv);
        /* deregister the usb driver */
        usb_deregister(&hso_driver);
        tty_driver_kref_put(tty_drv);
}

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

MODULE_AUTHOR(MOD_AUTHOR);
MODULE_DESCRIPTION(MOD_DESCRIPTION);
MODULE_LICENSE("GPL");

/* change the debug level (eg: insmod hso.ko debug=0x04) */
MODULE_PARM_DESC(debug, "debug level mask [0x01 | 0x02 | 0x04 | 0x08 | 0x10]");
module_param(debug, int, 0644);

/* 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, 0644);

/* disable network interface (eg: insmod hso.ko disable_net=1) */
MODULE_PARM_DESC(disable_net, "Disable the network interface");
module_param(disable_net, int, 0644);
Linux
