cdc-acm.c

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/*
 * cdc-acm.c
 *
 * Copyright (c) 1999 Armin Fuerst  <[email protected]>
 * Copyright (c) 1999 Pavel Machek  <[email protected]>
 * Copyright (c) 1999 Johannes Erdfelt  <[email protected]>
 * Copyright (c) 2000 Vojtech Pavlik    <[email protected]>
 * Copyright (c) 2004 Oliver Neukum <[email protected]>
 * Copyright (c) 2005 David Kubicek <[email protected]>
 * Copyright (c) 2011 Johan Hovold  <[email protected]>
 *
 * USB Abstract Control Model driver for USB modems and ISDN adapters
 *
 * Sponsored by SuSE
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#undef DEBUG
#undef VERBOSE_DEBUG

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/serial.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/cdc.h>
#include <asm/byteorder.h>
#include <asm/unaligned.h>
#include <linux/list.h>

#include "cdc-acm.h"


#define DRIVER_AUTHOR "Armin Fuerst, Pavel Machek, Johannes Erdfelt, Vojtech Pavlik, David Kubicek, Johan Hovold"
#define DRIVER_DESC "USB Abstract Control Model driver for USB modems and ISDN adapters"

static struct usb_driver acm_driver;
static struct tty_driver *acm_tty_driver;
static struct acm *acm_table[ACM_TTY_MINORS];

static DEFINE_MUTEX(acm_table_lock);

/*
 * acm_table accessors
 */

/*
 * Look up an ACM structure by index. If found and not disconnected, increment
 * its refcount and return it with its mutex held.
 */
static struct acm *acm_get_by_index(unsigned index)
{
    struct acm *acm;

    mutex_lock(&acm_table_lock);
    acm = acm_table[index];
    if (acm) {
        mutex_lock(&acm->mutex);
        if (acm->disconnected) {
            mutex_unlock(&acm->mutex);
            acm = NULL;
        } else {
            tty_port_get(&acm->port);
            mutex_unlock(&acm->mutex);
        }
    }
    mutex_unlock(&acm_table_lock);
    return acm;
}

/*
 * Try to find an available minor number and if found, associate it with 'acm'.
 */
static int acm_alloc_minor(struct acm *acm)
{
    int minor;

    mutex_lock(&acm_table_lock);
    for (minor = 0; minor < ACM_TTY_MINORS; minor++) {
        if (!acm_table[minor]) {
            acm_table[minor] = acm;
            break;
        }
    }
    mutex_unlock(&acm_table_lock);

    return minor;
}

/* Release the minor number associated with 'acm'.  */
static void acm_release_minor(struct acm *acm)
{
    mutex_lock(&acm_table_lock);
    acm_table[acm->minor] = NULL;
    mutex_unlock(&acm_table_lock);
}

/*
 * Functions for ACM control messages.
 */

static int acm_ctrl_msg(struct acm *acm, int request, int value,
                            void *buf, int len)
{
    int retval = usb_control_msg(acm->dev, usb_sndctrlpipe(acm->dev, 0),
        request, USB_RT_ACM, value,
        acm->control->altsetting[0].desc.bInterfaceNumber,
        buf, len, 5000);
    dev_dbg(&acm->control->dev,
            "%s - rq 0x%02x, val %#x, len %#x, result %d\n",
            __func__, request, value, len, retval);
    return retval < 0 ? retval : 0;
}

/* devices aren't required to support these requests.
 * the cdc acm descriptor tells whether they do...
 */
#define acm_set_control(acm, control) \
    acm_ctrl_msg(acm, USB_CDC_REQ_SET_CONTROL_LINE_STATE, control, NULL, 0)
#define acm_set_line(acm, line) \
    acm_ctrl_msg(acm, USB_CDC_REQ_SET_LINE_CODING, 0, line, sizeof *(line))
#define acm_send_break(acm, ms) \
    acm_ctrl_msg(acm, USB_CDC_REQ_SEND_BREAK, ms, NULL, 0)

/*
 * Write buffer management.
 * All of these assume proper locks taken by the caller.
 */

static int acm_wb_alloc(struct acm *acm)
{
    int i, wbn;
    struct acm_wb *wb;

    wbn = 0;
    i = 0;
    for (;;) {
        wb = &acm->wb[wbn];
        if (!wb->use) {
            wb->use = 1;
            return wbn;
        }
        wbn = (wbn + 1) % ACM_NW;
        if (++i >= ACM_NW)
            return -1;
    }
}

static int acm_wb_is_avail(struct acm *acm)
{
    int i, n;
    unsigned long flags;

    n = ACM_NW;
    spin_lock_irqsave(&acm->write_lock, flags);
    for (i = 0; i < ACM_NW; i++)
        n -= acm->wb[i].use;
    spin_unlock_irqrestore(&acm->write_lock, flags);
    return n;
}

/*
 * Finish write. Caller must hold acm->write_lock
 */
static void acm_write_done(struct acm *acm, struct acm_wb *wb)
{
    wb->use = 0;
    acm->transmitting--;
    usb_autopm_put_interface_async(acm->control);
}

/*
 * Poke write.
 *
 * the caller is responsible for locking
 */

static int acm_start_wb(struct acm *acm, struct acm_wb *wb)
{
    int rc;

    acm->transmitting++;

    wb->urb->transfer_buffer = wb->buf;
    wb->urb->transfer_dma = wb->dmah;
    wb->urb->transfer_buffer_length = wb->len;
    wb->urb->dev = acm->dev;

    rc = usb_submit_urb(wb->urb, GFP_ATOMIC);
    if (rc < 0) {
        dev_err(&acm->data->dev,
            "%s - usb_submit_urb(write bulk) failed: %d\n",
            __func__, rc);
        acm_write_done(acm, wb);
    }
    return rc;
}

static int acm_write_start(struct acm *acm, int wbn)
{
    unsigned long flags;
    struct acm_wb *wb = &acm->wb[wbn];
    int rc;

    spin_lock_irqsave(&acm->write_lock, flags);
    if (!acm->dev) {
        wb->use = 0;
        spin_unlock_irqrestore(&acm->write_lock, flags);
        return -ENODEV;
    }

    dev_vdbg(&acm->data->dev, "%s - susp_count %d\n", __func__,
                            acm->susp_count);
    usb_autopm_get_interface_async(acm->control);
    if (acm->susp_count) {
        if (!acm->delayed_wb)
            acm->delayed_wb = wb;
        else
            usb_autopm_put_interface_async(acm->control);
        spin_unlock_irqrestore(&acm->write_lock, flags);
        return 0;   /* A white lie */
    }
    usb_mark_last_busy(acm->dev);

    rc = acm_start_wb(acm, wb);
    spin_unlock_irqrestore(&acm->write_lock, flags);

    return rc;

}
/*
 * attributes exported through sysfs
 */
static ssize_t show_caps
(struct device *dev, struct device_attribute *attr, char *buf)
{
    struct usb_interface *intf = to_usb_interface(dev);
    struct acm *acm = usb_get_intfdata(intf);

    return sprintf(buf, "%d", acm->ctrl_caps);
}
static DEVICE_ATTR(bmCapabilities, S_IRUGO, show_caps, NULL);

static ssize_t show_country_codes
(struct device *dev, struct device_attribute *attr, char *buf)
{
    struct usb_interface *intf = to_usb_interface(dev);
    struct acm *acm = usb_get_intfdata(intf);

    memcpy(buf, acm->country_codes, acm->country_code_size);
    return acm->country_code_size;
}

static DEVICE_ATTR(wCountryCodes, S_IRUGO, show_country_codes, NULL);

static ssize_t show_country_rel_date
(struct device *dev, struct device_attribute *attr, char *buf)
{
    struct usb_interface *intf = to_usb_interface(dev);
    struct acm *acm = usb_get_intfdata(intf);

    return sprintf(buf, "%d", acm->country_rel_date);
}

static DEVICE_ATTR(iCountryCodeRelDate, S_IRUGO, show_country_rel_date, NULL);
/*
 * Interrupt handlers for various ACM device responses
 */

/* control interface reports status changes with "interrupt" transfers */
static void acm_ctrl_irq(struct urb *urb)
{
    struct acm *acm = urb->context;
    struct usb_cdc_notification *dr = urb->transfer_buffer;
    struct tty_struct *tty;
    unsigned char *data;
    int newctrl;
    int retval;
    int status = urb->status;

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

    usb_mark_last_busy(acm->dev);

    data = (unsigned char *)(dr + 1);
    switch (dr->bNotificationType) {
    case USB_CDC_NOTIFY_NETWORK_CONNECTION:
        dev_dbg(&acm->control->dev, "%s - network connection: %d\n",
                            __func__, dr->wValue);
        break;

    case USB_CDC_NOTIFY_SERIAL_STATE:
        tty = tty_port_tty_get(&acm->port);
        newctrl = get_unaligned_le16(data);

        if (tty) {
            if (!acm->clocal &&
                (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
                dev_dbg(&acm->control->dev,
                    "%s - calling hangup\n", __func__);
                tty_hangup(tty);
            }
            tty_kref_put(tty);
        }

        acm->ctrlin = newctrl;

        dev_dbg(&acm->control->dev,
            "%s - input control lines: dcd%c dsr%c break%c "
            "ring%c framing%c parity%c overrun%c\n",
            __func__,
            acm->ctrlin & ACM_CTRL_DCD ? '+' : '-',
            acm->ctrlin & ACM_CTRL_DSR ? '+' : '-',
            acm->ctrlin & ACM_CTRL_BRK ? '+' : '-',
            acm->ctrlin & ACM_CTRL_RI  ? '+' : '-',
            acm->ctrlin & ACM_CTRL_FRAMING ? '+' : '-',
            acm->ctrlin & ACM_CTRL_PARITY ? '+' : '-',
            acm->ctrlin & ACM_CTRL_OVERRUN ? '+' : '-');
            break;

    default:
        dev_dbg(&acm->control->dev,
            "%s - unknown notification %d received: index %d "
            "len %d data0 %d data1 %d\n",
            __func__,
            dr->bNotificationType, dr->wIndex,
            dr->wLength, data[0], data[1]);
        break;
    }
exit:
    retval = usb_submit_urb(urb, GFP_ATOMIC);
    if (retval)
        dev_err(&acm->control->dev, "%s - usb_submit_urb failed: %d\n",
                            __func__, retval);
}

static int acm_submit_read_urb(struct acm *acm, int index, gfp_t mem_flags)
{
    int res;

    if (!test_and_clear_bit(index, &acm->read_urbs_free))
        return 0;

    dev_vdbg(&acm->data->dev, "%s - urb %d\n", __func__, index);

    res = usb_submit_urb(acm->read_urbs[index], mem_flags);
    if (res) {
        if (res != -EPERM) {
            dev_err(&acm->data->dev,
                    "%s - usb_submit_urb failed: %d\n",
                    __func__, res);
        }
        set_bit(index, &acm->read_urbs_free);
        return res;
    }

    return 0;
}

static int acm_submit_read_urbs(struct acm *acm, gfp_t mem_flags)
{
    int res;
    int i;

    for (i = 0; i < acm->rx_buflimit; ++i) {
        res = acm_submit_read_urb(acm, i, mem_flags);
        if (res)
            return res;
    }

    return 0;
}

static void acm_process_read_urb(struct acm *acm, struct urb *urb)
{
    struct tty_struct *tty;

    if (!urb->actual_length)
        return;

    tty = tty_port_tty_get(&acm->port);
    if (!tty)
        return;

    tty_insert_flip_string(tty, urb->transfer_buffer, urb->actual_length);
    tty_flip_buffer_push(tty);

    tty_kref_put(tty);
}

static void acm_read_bulk_callback(struct urb *urb)
{
    struct acm_rb *rb = urb->context;
    struct acm *acm = rb->instance;
    unsigned long flags;

    dev_vdbg(&acm->data->dev, "%s - urb %d, len %d\n", __func__,
                    rb->index, urb->actual_length);
    set_bit(rb->index, &acm->read_urbs_free);

    if (!acm->dev) {
        dev_dbg(&acm->data->dev, "%s - disconnected\n", __func__);
        return;
    }
    usb_mark_last_busy(acm->dev);

    if (urb->status) {
        dev_dbg(&acm->data->dev, "%s - non-zero urb status: %d\n",
                            __func__, urb->status);
        return;
    }
    acm_process_read_urb(acm, urb);

    /* throttle device if requested by tty */
    spin_lock_irqsave(&acm->read_lock, flags);
    acm->throttled = acm->throttle_req;
    if (!acm->throttled && !acm->susp_count) {
        spin_unlock_irqrestore(&acm->read_lock, flags);
        acm_submit_read_urb(acm, rb->index, GFP_ATOMIC);
    } else {
        spin_unlock_irqrestore(&acm->read_lock, flags);
    }
}

/* data interface wrote those outgoing bytes */
static void acm_write_bulk(struct urb *urb)
{
    struct acm_wb *wb = urb->context;
    struct acm *acm = wb->instance;
    unsigned long flags;

    if (urb->status || (urb->actual_length != urb->transfer_buffer_length))
        dev_vdbg(&acm->data->dev, "%s - len %d/%d, status %d\n",
            __func__,
            urb->actual_length,
            urb->transfer_buffer_length,
            urb->status);

    spin_lock_irqsave(&acm->write_lock, flags);
    acm_write_done(acm, wb);
    spin_unlock_irqrestore(&acm->write_lock, flags);
    schedule_work(&acm->work);
}

static void acm_softint(struct work_struct *work)
{
    struct acm *acm = container_of(work, struct acm, work);
    struct tty_struct *tty;

    dev_vdbg(&acm->data->dev, "%s\n", __func__);

    tty = tty_port_tty_get(&acm->port);
    if (!tty)
        return;
    tty_wakeup(tty);
    tty_kref_put(tty);
}

/*
 * TTY handlers
 */

static int acm_tty_install(struct tty_driver *driver, struct tty_struct *tty)
{
    struct acm *acm;
    int retval;

    dev_dbg(tty->dev, "%s\n", __func__);

    acm = acm_get_by_index(tty->index);
    if (!acm)
        return -ENODEV;

    retval = tty_standard_install(driver, tty);
    if (retval)
        goto error_init_termios;

    tty->driver_data = acm;

    return 0;

error_init_termios:
    tty_port_put(&acm->port);
    return retval;
}

static int acm_tty_open(struct tty_struct *tty, struct file *filp)
{
    struct acm *acm = tty->driver_data;

    dev_dbg(tty->dev, "%s\n", __func__);

    return tty_port_open(&acm->port, tty, filp);
}

static int acm_port_activate(struct tty_port *port, struct tty_struct *tty)
{
    struct acm *acm = container_of(port, struct acm, port);
    int retval = -ENODEV;

    dev_dbg(&acm->control->dev, "%s\n", __func__);

    mutex_lock(&acm->mutex);
    if (acm->disconnected)
        goto disconnected;

    retval = usb_autopm_get_interface(acm->control);
    if (retval)
        goto error_get_interface;

    /*
     * FIXME: Why do we need this? Allocating 64K of physically contiguous
     * memory is really nasty...
     */
    set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
    acm->control->needs_remote_wakeup = 1;

    acm->ctrlurb->dev = acm->dev;
    if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) {
        dev_err(&acm->control->dev,
            "%s - usb_submit_urb(ctrl irq) failed\n", __func__);
        goto error_submit_urb;
    }

    acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS;
    if (acm_set_control(acm, acm->ctrlout) < 0 &&
        (acm->ctrl_caps & USB_CDC_CAP_LINE))
        goto error_set_control;

    usb_autopm_put_interface(acm->control);

    /*
     * Unthrottle device in case the TTY was closed while throttled.
     */
    spin_lock_irq(&acm->read_lock);
    acm->throttled = 0;
    acm->throttle_req = 0;
    spin_unlock_irq(&acm->read_lock);

    if (acm_submit_read_urbs(acm, GFP_KERNEL))
        goto error_submit_read_urbs;

    mutex_unlock(&acm->mutex);

    return 0;

error_submit_read_urbs:
    acm->ctrlout = 0;
    acm_set_control(acm, acm->ctrlout);
error_set_control:
    usb_kill_urb(acm->ctrlurb);
error_submit_urb:
    usb_autopm_put_interface(acm->control);
error_get_interface:
disconnected:
    mutex_unlock(&acm->mutex);
    return retval;
}

static void acm_port_destruct(struct tty_port *port)
{
    struct acm *acm = container_of(port, struct acm, port);

    dev_dbg(&acm->control->dev, "%s\n", __func__);

    tty_unregister_device(acm_tty_driver, acm->minor);
    acm_release_minor(acm);
    usb_put_intf(acm->control);
    kfree(acm->country_codes);
    kfree(acm);
}

static void acm_port_shutdown(struct tty_port *port)
{
    struct acm *acm = container_of(port, struct acm, port);
    int i;

    dev_dbg(&acm->control->dev, "%s\n", __func__);

    mutex_lock(&acm->mutex);
    if (!acm->disconnected) {
        usb_autopm_get_interface(acm->control);
        acm_set_control(acm, acm->ctrlout = 0);
        usb_kill_urb(acm->ctrlurb);
        for (i = 0; i < ACM_NW; i++)
            usb_kill_urb(acm->wb[i].urb);
        for (i = 0; i < acm->rx_buflimit; i++)
            usb_kill_urb(acm->read_urbs[i]);
        acm->control->needs_remote_wakeup = 0;
        usb_autopm_put_interface(acm->control);
    }
    mutex_unlock(&acm->mutex);
}

static void acm_tty_cleanup(struct tty_struct *tty)
{
    struct acm *acm = tty->driver_data;
    dev_dbg(&acm->control->dev, "%s\n", __func__);
    tty_port_put(&acm->port);
}

static void acm_tty_hangup(struct tty_struct *tty)
{
    struct acm *acm = tty->driver_data;
    dev_dbg(&acm->control->dev, "%s\n", __func__);
    tty_port_hangup(&acm->port);
}

static void acm_tty_close(struct tty_struct *tty, struct file *filp)
{
    struct acm *acm = tty->driver_data;
    dev_dbg(&acm->control->dev, "%s\n", __func__);
    tty_port_close(&acm->port, tty, filp);
}

static int acm_tty_write(struct tty_struct *tty,
                    const unsigned char *buf, int count)
{
    struct acm *acm = tty->driver_data;
    int stat;
    unsigned long flags;
    int wbn;
    struct acm_wb *wb;

    if (!count)
        return 0;

    dev_vdbg(&acm->data->dev, "%s - count %d\n", __func__, count);

    spin_lock_irqsave(&acm->write_lock, flags);
    wbn = acm_wb_alloc(acm);
    if (wbn < 0) {
        spin_unlock_irqrestore(&acm->write_lock, flags);
        return 0;
    }
    wb = &acm->wb[wbn];

    count = (count > acm->writesize) ? acm->writesize : count;
    dev_vdbg(&acm->data->dev, "%s - write %d\n", __func__, count);
    memcpy(wb->buf, buf, count);
    wb->len = count;
    spin_unlock_irqrestore(&acm->write_lock, flags);

    stat = acm_write_start(acm, wbn);
    if (stat < 0)
        return stat;
    return count;
}

static int acm_tty_write_room(struct tty_struct *tty)
{
    struct acm *acm = tty->driver_data;
    /*
     * Do not let the line discipline to know that we have a reserve,
     * or it might get too enthusiastic.
     */
    return acm_wb_is_avail(acm) ? acm->writesize : 0;
}

static int acm_tty_chars_in_buffer(struct tty_struct *tty)
{
    struct acm *acm = tty->driver_data;
    /*
     * if the device was unplugged then any remaining characters fell out
     * of the connector ;)
     */
    if (acm->disconnected)
        return 0;
    /*
     * This is inaccurate (overcounts), but it works.
     */
    return (ACM_NW - acm_wb_is_avail(acm)) * acm->writesize;
}

static void acm_tty_throttle(struct tty_struct *tty)
{
    struct acm *acm = tty->driver_data;

    spin_lock_irq(&acm->read_lock);
    acm->throttle_req = 1;
    spin_unlock_irq(&acm->read_lock);
}

static void acm_tty_unthrottle(struct tty_struct *tty)
{
    struct acm *acm = tty->driver_data;
    unsigned int was_throttled;

    spin_lock_irq(&acm->read_lock);
    was_throttled = acm->throttled;
    acm->throttled = 0;
    acm->throttle_req = 0;
    spin_unlock_irq(&acm->read_lock);

    if (was_throttled)
        acm_submit_read_urbs(acm, GFP_KERNEL);
}

static int acm_tty_break_ctl(struct tty_struct *tty, int state)
{
    struct acm *acm = tty->driver_data;
    int retval;

    retval = acm_send_break(acm, state ? 0xffff : 0);
    if (retval < 0)
        dev_dbg(&acm->control->dev, "%s - send break failed\n",
                                __func__);
    return retval;
}

static int acm_tty_tiocmget(struct tty_struct *tty)
{
    struct acm *acm = tty->driver_data;

    return (acm->ctrlout & ACM_CTRL_DTR ? TIOCM_DTR : 0) |
           (acm->ctrlout & ACM_CTRL_RTS ? TIOCM_RTS : 0) |
           (acm->ctrlin  & ACM_CTRL_DSR ? TIOCM_DSR : 0) |
           (acm->ctrlin  & ACM_CTRL_RI  ? TIOCM_RI  : 0) |
           (acm->ctrlin  & ACM_CTRL_DCD ? TIOCM_CD  : 0) |
           TIOCM_CTS;
}

static int acm_tty_tiocmset(struct tty_struct *tty,
                unsigned int set, unsigned int clear)
{
    struct acm *acm = tty->driver_data;
    unsigned int newctrl;

    newctrl = acm->ctrlout;
    set = (set & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
                    (set & TIOCM_RTS ? ACM_CTRL_RTS : 0);
    clear = (clear & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
                    (clear & TIOCM_RTS ? ACM_CTRL_RTS : 0);

    newctrl = (newctrl & ~clear) | set;

    if (acm->ctrlout == newctrl)
        return 0;
    return acm_set_control(acm, acm->ctrlout = newctrl);
}

static int get_serial_info(struct acm *acm, struct serial_struct __user *info)
{
    struct serial_struct tmp;

    if (!info)
        return -EINVAL;

    memset(&tmp, 0, sizeof(tmp));
    tmp.flags = ASYNC_LOW_LATENCY;
    tmp.xmit_fifo_size = acm->writesize;
    tmp.baud_base = le32_to_cpu(acm->line.dwDTERate);
    tmp.close_delay = acm->port.close_delay / 10;
    tmp.closing_wait = acm->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
                ASYNC_CLOSING_WAIT_NONE :
                acm->port.closing_wait / 10;

    if (copy_to_user(info, &tmp, sizeof(tmp)))
        return -EFAULT;
    else
        return 0;
}

static int set_serial_info(struct acm *acm,
                struct serial_struct __user *newinfo)
{
    struct serial_struct new_serial;
    unsigned int closing_wait, close_delay;
    int retval = 0;

    if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
        return -EFAULT;

    close_delay = new_serial.close_delay * 10;
    closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
            ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;

    mutex_lock(&acm->port.mutex);

    if (!capable(CAP_SYS_ADMIN)) {
        if ((close_delay != acm->port.close_delay) ||
            (closing_wait != acm->port.closing_wait))
            retval = -EPERM;
        else
            retval = -EOPNOTSUPP;
    } else {
        acm->port.close_delay  = close_delay;
        acm->port.closing_wait = closing_wait;
    }

    mutex_unlock(&acm->port.mutex);
    return retval;
}

static int acm_tty_ioctl(struct tty_struct *tty,
                    unsigned int cmd, unsigned long arg)
{
    struct acm *acm = tty->driver_data;
    int rv = -ENOIOCTLCMD;

    switch (cmd) {
    case TIOCGSERIAL: /* gets serial port data */
        rv = get_serial_info(acm, (struct serial_struct __user *) arg);
        break;
    case TIOCSSERIAL:
        rv = set_serial_info(acm, (struct serial_struct __user *) arg);
        break;
    }

    return rv;
}

static const __u32 acm_tty_speed[] = {
    0, 50, 75, 110, 134, 150, 200, 300, 600,
    1200, 1800, 2400, 4800, 9600, 19200, 38400,
    57600, 115200, 230400, 460800, 500000, 576000,
    921600, 1000000, 1152000, 1500000, 2000000,
    2500000, 3000000, 3500000, 4000000
};

static void acm_tty_set_termios(struct tty_struct *tty,
                        struct ktermios *termios_old)
{
    struct acm *acm = tty->driver_data;
    struct ktermios *termios = &tty->termios;
    struct usb_cdc_line_coding newline;
    int newctrl = acm->ctrlout;

    newline.dwDTERate = cpu_to_le32(tty_get_baud_rate(tty));
    newline.bCharFormat = termios->c_cflag & CSTOPB ? 2 : 0;
    newline.bParityType = termios->c_cflag & PARENB ?
                (termios->c_cflag & PARODD ? 1 : 2) +
                (termios->c_cflag & CMSPAR ? 2 : 0) : 0;
    switch (termios->c_cflag & CSIZE) {
    case CS5:
        newline.bDataBits = 5;
        break;
    case CS6:
        newline.bDataBits = 6;
        break;
    case CS7:
        newline.bDataBits = 7;
        break;
    case CS8:
    default:
        newline.bDataBits = 8;
        break;
    }
    /* FIXME: Needs to clear unsupported bits in the termios */
    acm->clocal = ((termios->c_cflag & CLOCAL) != 0);

    if (!newline.dwDTERate) {
        newline.dwDTERate = acm->line.dwDTERate;
        newctrl &= ~ACM_CTRL_DTR;
    } else
        newctrl |=  ACM_CTRL_DTR;

    if (newctrl != acm->ctrlout)
        acm_set_control(acm, acm->ctrlout = newctrl);

    if (memcmp(&acm->line, &newline, sizeof newline)) {
        memcpy(&acm->line, &newline, sizeof newline);
        dev_dbg(&acm->control->dev, "%s - set line: %d %d %d %d\n",
            __func__,
            le32_to_cpu(newline.dwDTERate),
            newline.bCharFormat, newline.bParityType,
            newline.bDataBits);
        acm_set_line(acm, &acm->line);
    }
}

static const struct tty_port_operations acm_port_ops = {
    .shutdown = acm_port_shutdown,
    .activate = acm_port_activate,
    .destruct = acm_port_destruct,
};

/*
 * USB probe and disconnect routines.
 */

/* Little helpers: write/read buffers free */
static void acm_write_buffers_free(struct acm *acm)
{
    int i;
    struct acm_wb *wb;
    struct usb_device *usb_dev = interface_to_usbdev(acm->control);

    for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++)
        usb_free_coherent(usb_dev, acm->writesize, wb->buf, wb->dmah);
}

static void acm_read_buffers_free(struct acm *acm)
{
    struct usb_device *usb_dev = interface_to_usbdev(acm->control);
    int i;

    for (i = 0; i < acm->rx_buflimit; i++)
        usb_free_coherent(usb_dev, acm->readsize,
              acm->read_buffers[i].base, acm->read_buffers[i].dma);
}

/* Little helper: write buffers allocate */
static int acm_write_buffers_alloc(struct acm *acm)
{
    int i;
    struct acm_wb *wb;

    for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++) {
        wb->buf = usb_alloc_coherent(acm->dev, acm->writesize, GFP_KERNEL,
            &wb->dmah);
        if (!wb->buf) {
            while (i != 0) {
                --i;
                --wb;
                usb_free_coherent(acm->dev, acm->writesize,
                    wb->buf, wb->dmah);
            }
            return -ENOMEM;
        }
    }
    return 0;
}

static int acm_probe(struct usb_interface *intf,
             const struct usb_device_id *id)
{
    struct usb_cdc_union_desc *union_header = NULL;
    struct usb_cdc_country_functional_desc *cfd = NULL;
    unsigned char *buffer = intf->altsetting->extra;
    int buflen = intf->altsetting->extralen;
    struct usb_interface *control_interface;
    struct usb_interface *data_interface;
    struct usb_endpoint_descriptor *epctrl = NULL;
    struct usb_endpoint_descriptor *epread = NULL;
    struct usb_endpoint_descriptor *epwrite = NULL;
    struct usb_device *usb_dev = interface_to_usbdev(intf);
    struct acm *acm;
    int minor;
    int ctrlsize, readsize;
    u8 *buf;
    u8 ac_management_function = 0;
    u8 call_management_function = 0;
    int call_interface_num = -1;
    int data_interface_num = -1;
    unsigned long quirks;
    int num_rx_buf;
    int i;
    int combined_interfaces = 0;

    /* normal quirks */
    quirks = (unsigned long)id->driver_info;
    num_rx_buf = (quirks == SINGLE_RX_URB) ? 1 : ACM_NR;

    /* handle quirks deadly to normal probing*/
    if (quirks == NO_UNION_NORMAL) {
        data_interface = usb_ifnum_to_if(usb_dev, 1);
        control_interface = usb_ifnum_to_if(usb_dev, 0);
        goto skip_normal_probe;
    }

    /* normal probing*/
    if (!buffer) {
        dev_err(&intf->dev, "Weird descriptor references\n");
        return -EINVAL;
    }

    if (!buflen) {
        if (intf->cur_altsetting->endpoint &&
                intf->cur_altsetting->endpoint->extralen &&
                intf->cur_altsetting->endpoint->extra) {
            dev_dbg(&intf->dev,
                "Seeking extra descriptors on endpoint\n");
            buflen = intf->cur_altsetting->endpoint->extralen;
            buffer = intf->cur_altsetting->endpoint->extra;
        } else {
            dev_err(&intf->dev,
                "Zero length descriptor references\n");
            return -EINVAL;
        }
    }

    while (buflen > 0) {
        if (buffer[1] != USB_DT_CS_INTERFACE) {
            dev_err(&intf->dev, "skipping garbage\n");
            goto next_desc;
        }

        switch (buffer[2]) {
        case USB_CDC_UNION_TYPE: /* we've found it */
            if (union_header) {
                dev_err(&intf->dev, "More than one "
                    "union descriptor, skipping ...\n");
                goto next_desc;
            }
            union_header = (struct usb_cdc_union_desc *)buffer;
            break;
        case USB_CDC_COUNTRY_TYPE: /* export through sysfs*/
            cfd = (struct usb_cdc_country_functional_desc *)buffer;
            break;
        case USB_CDC_HEADER_TYPE: /* maybe check version */
            break; /* for now we ignore it */
        case USB_CDC_ACM_TYPE:
            ac_management_function = buffer[3];
            break;
        case USB_CDC_CALL_MANAGEMENT_TYPE:
            call_management_function = buffer[3];
            call_interface_num = buffer[4];
            if ((quirks & NOT_A_MODEM) == 0 && (call_management_function & 3) != 3)
                dev_err(&intf->dev, "This device cannot do calls on its own. It is not a modem.\n");
            break;
        default:
            /* there are LOTS more CDC descriptors that
             * could legitimately be found here.
             */
            dev_dbg(&intf->dev, "Ignoring descriptor: "
                    "type %02x, length %d\n",
                    buffer[2], buffer[0]);
            break;
        }
next_desc:
        buflen -= buffer[0];
        buffer += buffer[0];
    }

    if (!union_header) {
        if (call_interface_num > 0) {
            dev_dbg(&intf->dev, "No union descriptor, using call management descriptor\n");
            /* quirks for Droids MuIn LCD */
            if (quirks & NO_DATA_INTERFACE)
                data_interface = usb_ifnum_to_if(usb_dev, 0);
            else
                data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = call_interface_num));
            control_interface = intf;
        } else {
            if (intf->cur_altsetting->desc.bNumEndpoints != 3) {
                dev_dbg(&intf->dev,"No union descriptor, giving up\n");
                return -ENODEV;
            } else {
                dev_warn(&intf->dev,"No union descriptor, testing for castrated device\n");
                combined_interfaces = 1;
                control_interface = data_interface = intf;
                goto look_for_collapsed_interface;
            }
        }
    } else {
        control_interface = usb_ifnum_to_if(usb_dev, union_header->bMasterInterface0);
        data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = union_header->bSlaveInterface0));
        if (!control_interface || !data_interface) {
            dev_dbg(&intf->dev, "no interfaces\n");
            return -ENODEV;
        }
    }

    if (data_interface_num != call_interface_num)
        dev_dbg(&intf->dev, "Separate call control interface. That is not fully supported.\n");

    if (control_interface == data_interface) {
        /* some broken devices designed for windows work this way */
        dev_warn(&intf->dev,"Control and data interfaces are not separated!\n");
        combined_interfaces = 1;
        /* a popular other OS doesn't use it */
        quirks |= NO_CAP_LINE;
        if (data_interface->cur_altsetting->desc.bNumEndpoints != 3) {
            dev_err(&intf->dev, "This needs exactly 3 endpoints\n");
            return -EINVAL;
        }
look_for_collapsed_interface:
        for (i = 0; i < 3; i++) {
            struct usb_endpoint_descriptor *ep;
            ep = &data_interface->cur_altsetting->endpoint[i].desc;

            if (usb_endpoint_is_int_in(ep))
                epctrl = ep;
            else if (usb_endpoint_is_bulk_out(ep))
                epwrite = ep;
            else if (usb_endpoint_is_bulk_in(ep))
                epread = ep;
            else
                return -EINVAL;
        }
        if (!epctrl || !epread || !epwrite)
            return -ENODEV;
        else
            goto made_compressed_probe;
    }

skip_normal_probe:

    /*workaround for switched interfaces */
    if (data_interface->cur_altsetting->desc.bInterfaceClass
                        != CDC_DATA_INTERFACE_TYPE) {
        if (control_interface->cur_altsetting->desc.bInterfaceClass
                        == CDC_DATA_INTERFACE_TYPE) {
            struct usb_interface *t;
            dev_dbg(&intf->dev,
                "Your device has switched interfaces.\n");
            t = control_interface;
            control_interface = data_interface;
            data_interface = t;
        } else {
            return -EINVAL;
        }
    }

    /* Accept probe requests only for the control interface */
    if (!combined_interfaces && intf != control_interface)
        return -ENODEV;

    if (!combined_interfaces && usb_interface_claimed(data_interface)) {
        /* valid in this context */
        dev_dbg(&intf->dev, "The data interface isn't available\n");
        return -EBUSY;
    }


    if (data_interface->cur_altsetting->desc.bNumEndpoints < 2 ||
        control_interface->cur_altsetting->desc.bNumEndpoints == 0)
        return -EINVAL;

    epctrl = &control_interface->cur_altsetting->endpoint[0].desc;
    epread = &data_interface->cur_altsetting->endpoint[0].desc;
    epwrite = &data_interface->cur_altsetting->endpoint[1].desc;


    /* workaround for switched endpoints */
    if (!usb_endpoint_dir_in(epread)) {
        /* descriptors are swapped */
        struct usb_endpoint_descriptor *t;
        dev_dbg(&intf->dev,
            "The data interface has switched endpoints\n");
        t = epread;
        epread = epwrite;
        epwrite = t;
    }
made_compressed_probe:
    dev_dbg(&intf->dev, "interfaces are valid\n");

    acm = kzalloc(sizeof(struct acm), GFP_KERNEL);
    if (acm == NULL) {
        dev_err(&intf->dev, "out of memory (acm kzalloc)\n");
        goto alloc_fail;
    }

    minor = acm_alloc_minor(acm);
    if (minor == ACM_TTY_MINORS) {
        dev_err(&intf->dev, "no more free acm devices\n");
        kfree(acm);
        return -ENODEV;
    }

    ctrlsize = usb_endpoint_maxp(epctrl);
    readsize = usb_endpoint_maxp(epread) *
                (quirks == SINGLE_RX_URB ? 1 : 2);
    acm->combined_interfaces = combined_interfaces;
    acm->writesize = usb_endpoint_maxp(epwrite) * 20;
    acm->control = control_interface;
    acm->data = data_interface;
    acm->minor = minor;
    acm->dev = usb_dev;
    acm->ctrl_caps = ac_management_function;
    if (quirks & NO_CAP_LINE)
        acm->ctrl_caps &= ~USB_CDC_CAP_LINE;
    acm->ctrlsize = ctrlsize;
    acm->readsize = readsize;
    acm->rx_buflimit = num_rx_buf;
    INIT_WORK(&acm->work, acm_softint);
    spin_lock_init(&acm->write_lock);
    spin_lock_init(&acm->read_lock);
    mutex_init(&acm->mutex);
    acm->rx_endpoint = usb_rcvbulkpipe(usb_dev, epread->bEndpointAddress);
    acm->is_int_ep = usb_endpoint_xfer_int(epread);
    if (acm->is_int_ep)
        acm->bInterval = epread->bInterval;
    tty_port_init(&acm->port);
    acm->port.ops = &acm_port_ops;

    buf = usb_alloc_coherent(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
    if (!buf) {
        dev_err(&intf->dev, "out of memory (ctrl buffer alloc)\n");
        goto alloc_fail2;
    }
    acm->ctrl_buffer = buf;

    if (acm_write_buffers_alloc(acm) < 0) {
        dev_err(&intf->dev, "out of memory (write buffer alloc)\n");
        goto alloc_fail4;
    }

    acm->ctrlurb = usb_alloc_urb(0, GFP_KERNEL);
    if (!acm->ctrlurb) {
        dev_err(&intf->dev, "out of memory (ctrlurb kmalloc)\n");
        goto alloc_fail5;
    }
    for (i = 0; i < num_rx_buf; i++) {
        struct acm_rb *rb = &(acm->read_buffers[i]);
        struct urb *urb;

        rb->base = usb_alloc_coherent(acm->dev, readsize, GFP_KERNEL,
                                &rb->dma);
        if (!rb->base) {
            dev_err(&intf->dev, "out of memory "
                    "(read bufs usb_alloc_coherent)\n");
            goto alloc_fail6;
        }
        rb->index = i;
        rb->instance = acm;

        urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!urb) {
            dev_err(&intf->dev,
                "out of memory (read urbs usb_alloc_urb)\n");
            goto alloc_fail6;
        }
        urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
        urb->transfer_dma = rb->dma;
        if (acm->is_int_ep) {
            usb_fill_int_urb(urb, acm->dev,
                     acm->rx_endpoint,
                     rb->base,
                     acm->readsize,
                     acm_read_bulk_callback, rb,
                     acm->bInterval);
        } else {
            usb_fill_bulk_urb(urb, acm->dev,
                      acm->rx_endpoint,
                      rb->base,
                      acm->readsize,
                      acm_read_bulk_callback, rb);
        }

        acm->read_urbs[i] = urb;
        __set_bit(i, &acm->read_urbs_free);
    }
    for (i = 0; i < ACM_NW; i++) {
        struct acm_wb *snd = &(acm->wb[i]);

        snd->urb = usb_alloc_urb(0, GFP_KERNEL);
        if (snd->urb == NULL) {
            dev_err(&intf->dev,
                "out of memory (write urbs usb_alloc_urb)\n");
            goto alloc_fail7;
        }

        if (usb_endpoint_xfer_int(epwrite))
            usb_fill_int_urb(snd->urb, usb_dev,
                usb_sndintpipe(usb_dev, epwrite->bEndpointAddress),
                NULL, acm->writesize, acm_write_bulk, snd, epwrite->bInterval);
        else
            usb_fill_bulk_urb(snd->urb, usb_dev,
                usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress),
                NULL, acm->writesize, acm_write_bulk, snd);
        snd->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
        snd->instance = acm;
    }

    usb_set_intfdata(intf, acm);

    i = device_create_file(&intf->dev, &dev_attr_bmCapabilities);
    if (i < 0)
        goto alloc_fail7;

    if (cfd) { /* export the country data */
        acm->country_codes = kmalloc(cfd->bLength - 4, GFP_KERNEL);
        if (!acm->country_codes)
            goto skip_countries;
        acm->country_code_size = cfd->bLength - 4;
        memcpy(acm->country_codes, (u8 *)&cfd->wCountyCode0,
                            cfd->bLength - 4);
        acm->country_rel_date = cfd->iCountryCodeRelDate;

        i = device_create_file(&intf->dev, &dev_attr_wCountryCodes);
        if (i < 0) {
            kfree(acm->country_codes);
            acm->country_codes = NULL;
            acm->country_code_size = 0;
            goto skip_countries;
        }

        i = device_create_file(&intf->dev,
                        &dev_attr_iCountryCodeRelDate);
        if (i < 0) {
            device_remove_file(&intf->dev, &dev_attr_wCountryCodes);
            kfree(acm->country_codes);
            acm->country_codes = NULL;
            acm->country_code_size = 0;
            goto skip_countries;
        }
    }

skip_countries:
    usb_fill_int_urb(acm->ctrlurb, usb_dev,
             usb_rcvintpipe(usb_dev, epctrl->bEndpointAddress),
             acm->ctrl_buffer, ctrlsize, acm_ctrl_irq, acm,
             /* works around buggy devices */
             epctrl->bInterval ? epctrl->bInterval : 0xff);
    acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
    acm->ctrlurb->transfer_dma = acm->ctrl_dma;

    dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);

    acm_set_control(acm, acm->ctrlout);

    acm->line.dwDTERate = cpu_to_le32(9600);
    acm->line.bDataBits = 8;
    acm_set_line(acm, &acm->line);

    usb_driver_claim_interface(&acm_driver, data_interface, acm);
    usb_set_intfdata(data_interface, acm);

    usb_get_intf(control_interface);
    tty_port_register_device(&acm->port, acm_tty_driver, minor,
            &control_interface->dev);

    return 0;
alloc_fail7:
    for (i = 0; i < ACM_NW; i++)
        usb_free_urb(acm->wb[i].urb);
alloc_fail6:
    for (i = 0; i < num_rx_buf; i++)
        usb_free_urb(acm->read_urbs[i]);
    acm_read_buffers_free(acm);
    usb_free_urb(acm->ctrlurb);
alloc_fail5:
    acm_write_buffers_free(acm);
alloc_fail4:
    usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
alloc_fail2:
    acm_release_minor(acm);
    kfree(acm);
alloc_fail:
    return -ENOMEM;
}

static void stop_data_traffic(struct acm *acm)
{
    int i;

    dev_dbg(&acm->control->dev, "%s\n", __func__);

    usb_kill_urb(acm->ctrlurb);
    for (i = 0; i < ACM_NW; i++)
        usb_kill_urb(acm->wb[i].urb);
    for (i = 0; i < acm->rx_buflimit; i++)
        usb_kill_urb(acm->read_urbs[i]);

    cancel_work_sync(&acm->work);
}

static void acm_disconnect(struct usb_interface *intf)
{
    struct acm *acm = usb_get_intfdata(intf);
    struct usb_device *usb_dev = interface_to_usbdev(intf);
    struct tty_struct *tty;
    int i;

    dev_dbg(&intf->dev, "%s\n", __func__);

    /* sibling interface is already cleaning up */
    if (!acm)
        return;

    mutex_lock(&acm->mutex);
    acm->disconnected = true;
    if (acm->country_codes) {
        device_remove_file(&acm->control->dev,
                &dev_attr_wCountryCodes);
        device_remove_file(&acm->control->dev,
                &dev_attr_iCountryCodeRelDate);
    }
    device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
    usb_set_intfdata(acm->control, NULL);
    usb_set_intfdata(acm->data, NULL);
    mutex_unlock(&acm->mutex);

    tty = tty_port_tty_get(&acm->port);
    if (tty) {
        tty_vhangup(tty);
        tty_kref_put(tty);
    }

    stop_data_traffic(acm);

    usb_free_urb(acm->ctrlurb);
    for (i = 0; i < ACM_NW; i++)
        usb_free_urb(acm->wb[i].urb);
    for (i = 0; i < acm->rx_buflimit; i++)
        usb_free_urb(acm->read_urbs[i]);
    acm_write_buffers_free(acm);
    usb_free_coherent(usb_dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
    acm_read_buffers_free(acm);

    if (!acm->combined_interfaces)
        usb_driver_release_interface(&acm_driver, intf == acm->control ?
                    acm->data : acm->control);

    tty_port_put(&acm->port);
}

#ifdef CONFIG_PM
static int acm_suspend(struct usb_interface *intf, pm_message_t message)
{
    struct acm *acm = usb_get_intfdata(intf);
    int cnt;

    if (PMSG_IS_AUTO(message)) {
        int b;

        spin_lock_irq(&acm->write_lock);
        b = acm->transmitting;
        spin_unlock_irq(&acm->write_lock);
        if (b)
            return -EBUSY;
    }

    spin_lock_irq(&acm->read_lock);
    spin_lock(&acm->write_lock);
    cnt = acm->susp_count++;
    spin_unlock(&acm->write_lock);
    spin_unlock_irq(&acm->read_lock);

    if (cnt)
        return 0;

    if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags))
        stop_data_traffic(acm);

    return 0;
}

static int acm_resume(struct usb_interface *intf)
{
    struct acm *acm = usb_get_intfdata(intf);
    struct acm_wb *wb;
    int rv = 0;
    int cnt;

    spin_lock_irq(&acm->read_lock);
    acm->susp_count -= 1;
    cnt = acm->susp_count;
    spin_unlock_irq(&acm->read_lock);

    if (cnt)
        return 0;

    if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) {
        rv = usb_submit_urb(acm->ctrlurb, GFP_NOIO);

        spin_lock_irq(&acm->write_lock);
        if (acm->delayed_wb) {
            wb = acm->delayed_wb;
            acm->delayed_wb = NULL;
            spin_unlock_irq(&acm->write_lock);
            acm_start_wb(acm, wb);
        } else {
            spin_unlock_irq(&acm->write_lock);
        }

        /*
         * delayed error checking because we must
         * do the write path at all cost
         */
        if (rv < 0)
            goto err_out;

        rv = acm_submit_read_urbs(acm, GFP_NOIO);
    }

err_out:
    return rv;
}

static int acm_reset_resume(struct usb_interface *intf)
{
    struct acm *acm = usb_get_intfdata(intf);
    struct tty_struct *tty;

    if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) {
        tty = tty_port_tty_get(&acm->port);
        if (tty) {
            tty_hangup(tty);
            tty_kref_put(tty);
        }
    }

    return acm_resume(intf);
}

#endif /* CONFIG_PM */

#define NOKIA_PCSUITE_ACM_INFO(x) \
        USB_DEVICE_AND_INTERFACE_INFO(0x0421, x, \
        USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
        USB_CDC_ACM_PROTO_VENDOR)

#define SAMSUNG_PCSUITE_ACM_INFO(x) \
        USB_DEVICE_AND_INTERFACE_INFO(0x04e7, x, \
        USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
        USB_CDC_ACM_PROTO_VENDOR)

/*
 * USB driver structure.
 */

static const struct usb_device_id acm_ids[] = {
    /* quirky and broken devices */
    { USB_DEVICE(0x0870, 0x0001), /* Metricom GS Modem */
    .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
    },
    { USB_DEVICE(0x0e8d, 0x0003), /* FIREFLY, MediaTek Inc; [email protected] */
    .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
    },
    { USB_DEVICE(0x0e8d, 0x3329), /* MediaTek Inc GPS */
    .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
    },
    { USB_DEVICE(0x0482, 0x0203), /* KYOCERA AH-K3001V */
    .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
    },
    { USB_DEVICE(0x079b, 0x000f), /* BT On-Air USB MODEM */
    .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
    },
    { USB_DEVICE(0x0ace, 0x1602), /* ZyDAS 56K USB MODEM */
    .driver_info = SINGLE_RX_URB,
    },
    { USB_DEVICE(0x0ace, 0x1608), /* ZyDAS 56K USB MODEM */
    .driver_info = SINGLE_RX_URB, /* firmware bug */
    },
    { USB_DEVICE(0x0ace, 0x1611), /* ZyDAS 56K USB MODEM - new version */
    .driver_info = SINGLE_RX_URB, /* firmware bug */
    },
    { USB_DEVICE(0x22b8, 0x7000), /* Motorola Q Phone */
    .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
    },
    { USB_DEVICE(0x0803, 0x3095), /* Zoom Telephonics Model 3095F USB MODEM */
    .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
    },
    { USB_DEVICE(0x0572, 0x1321), /* Conexant USB MODEM CX93010 */
    .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
    },
    { USB_DEVICE(0x0572, 0x1324), /* Conexant USB MODEM RD02-D400 */
    .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
    },
    { USB_DEVICE(0x0572, 0x1328), /* Shiro / Aztech USB MODEM UM-3100 */
    .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
    },
    { USB_DEVICE(0x22b8, 0x6425), /* Motorola MOTOMAGX phones */
    },
    /* Motorola H24 HSPA module: */
    { USB_DEVICE(0x22b8, 0x2d91) }, /* modem                                */
    { USB_DEVICE(0x22b8, 0x2d92) }, /* modem           + diagnostics        */
    { USB_DEVICE(0x22b8, 0x2d93) }, /* modem + AT port                      */
    { USB_DEVICE(0x22b8, 0x2d95) }, /* modem + AT port + diagnostics        */
    { USB_DEVICE(0x22b8, 0x2d96) }, /* modem                         + NMEA */
    { USB_DEVICE(0x22b8, 0x2d97) }, /* modem           + diagnostics + NMEA */
    { USB_DEVICE(0x22b8, 0x2d99) }, /* modem + AT port               + NMEA */
    { USB_DEVICE(0x22b8, 0x2d9a) }, /* modem + AT port + diagnostics + NMEA */

    { USB_DEVICE(0x0572, 0x1329), /* Hummingbird huc56s (Conexant) */
    .driver_info = NO_UNION_NORMAL, /* union descriptor misplaced on
                       data interface instead of
                       communications interface.
                       Maybe we should define a new
                       quirk for this. */
    },
    { USB_DEVICE(0x0572, 0x1340), /* Conexant CX93010-2x UCMxx */
    .driver_info = NO_UNION_NORMAL,
    },
    { USB_DEVICE(0x1bbb, 0x0003), /* Alcatel OT-I650 */
    .driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
    },
    { USB_DEVICE(0x1576, 0x03b1), /* Maretron USB100 */
    .driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
    },

    /* Nokia S60 phones expose two ACM channels. The first is
     * a modem and is picked up by the standard AT-command
     * information below. The second is 'vendor-specific' but
     * is treated as a serial device at the S60 end, so we want
     * to expose it on Linux too. */
    { NOKIA_PCSUITE_ACM_INFO(0x042D), }, /* Nokia 3250 */
    { NOKIA_PCSUITE_ACM_INFO(0x04D8), }, /* Nokia 5500 Sport */
    { NOKIA_PCSUITE_ACM_INFO(0x04C9), }, /* Nokia E50 */
    { NOKIA_PCSUITE_ACM_INFO(0x0419), }, /* Nokia E60 */
    { NOKIA_PCSUITE_ACM_INFO(0x044D), }, /* Nokia E61 */
    { NOKIA_PCSUITE_ACM_INFO(0x0001), }, /* Nokia E61i */
    { NOKIA_PCSUITE_ACM_INFO(0x0475), }, /* Nokia E62 */
    { NOKIA_PCSUITE_ACM_INFO(0x0508), }, /* Nokia E65 */
    { NOKIA_PCSUITE_ACM_INFO(0x0418), }, /* Nokia E70 */
    { NOKIA_PCSUITE_ACM_INFO(0x0425), }, /* Nokia N71 */
    { NOKIA_PCSUITE_ACM_INFO(0x0486), }, /* Nokia N73 */
    { NOKIA_PCSUITE_ACM_INFO(0x04DF), }, /* Nokia N75 */
    { NOKIA_PCSUITE_ACM_INFO(0x000e), }, /* Nokia N77 */
    { NOKIA_PCSUITE_ACM_INFO(0x0445), }, /* Nokia N80 */
    { NOKIA_PCSUITE_ACM_INFO(0x042F), }, /* Nokia N91 & N91 8GB */
    { NOKIA_PCSUITE_ACM_INFO(0x048E), }, /* Nokia N92 */
    { NOKIA_PCSUITE_ACM_INFO(0x0420), }, /* Nokia N93 */
    { NOKIA_PCSUITE_ACM_INFO(0x04E6), }, /* Nokia N93i  */
    { NOKIA_PCSUITE_ACM_INFO(0x04B2), }, /* Nokia 5700 XpressMusic */
    { NOKIA_PCSUITE_ACM_INFO(0x0134), }, /* Nokia 6110 Navigator (China) */
    { NOKIA_PCSUITE_ACM_INFO(0x046E), }, /* Nokia 6110 Navigator */
    { NOKIA_PCSUITE_ACM_INFO(0x002f), }, /* Nokia 6120 classic &  */
    { NOKIA_PCSUITE_ACM_INFO(0x0088), }, /* Nokia 6121 classic */
    { NOKIA_PCSUITE_ACM_INFO(0x00fc), }, /* Nokia 6124 classic */
    { NOKIA_PCSUITE_ACM_INFO(0x0042), }, /* Nokia E51 */
    { NOKIA_PCSUITE_ACM_INFO(0x00b0), }, /* Nokia E66 */
    { NOKIA_PCSUITE_ACM_INFO(0x00ab), }, /* Nokia E71 */
    { NOKIA_PCSUITE_ACM_INFO(0x0481), }, /* Nokia N76 */
    { NOKIA_PCSUITE_ACM_INFO(0x0007), }, /* Nokia N81 & N81 8GB */
    { NOKIA_PCSUITE_ACM_INFO(0x0071), }, /* Nokia N82 */
    { NOKIA_PCSUITE_ACM_INFO(0x04F0), }, /* Nokia N95 & N95-3 NAM */
    { NOKIA_PCSUITE_ACM_INFO(0x0070), }, /* Nokia N95 8GB  */
    { NOKIA_PCSUITE_ACM_INFO(0x00e9), }, /* Nokia 5320 XpressMusic */
    { NOKIA_PCSUITE_ACM_INFO(0x0099), }, /* Nokia 6210 Navigator, RM-367 */
    { NOKIA_PCSUITE_ACM_INFO(0x0128), }, /* Nokia 6210 Navigator, RM-419 */
    { NOKIA_PCSUITE_ACM_INFO(0x008f), }, /* Nokia 6220 Classic */
    { NOKIA_PCSUITE_ACM_INFO(0x00a0), }, /* Nokia 6650 */
    { NOKIA_PCSUITE_ACM_INFO(0x007b), }, /* Nokia N78 */
    { NOKIA_PCSUITE_ACM_INFO(0x0094), }, /* Nokia N85 */
    { NOKIA_PCSUITE_ACM_INFO(0x003a), }, /* Nokia N96 & N96-3  */
    { NOKIA_PCSUITE_ACM_INFO(0x00e9), }, /* Nokia 5320 XpressMusic */
    { NOKIA_PCSUITE_ACM_INFO(0x0108), }, /* Nokia 5320 XpressMusic 2G */
    { NOKIA_PCSUITE_ACM_INFO(0x01f5), }, /* Nokia N97, RM-505 */
    { NOKIA_PCSUITE_ACM_INFO(0x02e3), }, /* Nokia 5230, RM-588 */
    { NOKIA_PCSUITE_ACM_INFO(0x0178), }, /* Nokia E63 */
    { NOKIA_PCSUITE_ACM_INFO(0x010e), }, /* Nokia E75 */
    { NOKIA_PCSUITE_ACM_INFO(0x02d9), }, /* Nokia 6760 Slide */
    { NOKIA_PCSUITE_ACM_INFO(0x01d0), }, /* Nokia E52 */
    { NOKIA_PCSUITE_ACM_INFO(0x0223), }, /* Nokia E72 */
    { NOKIA_PCSUITE_ACM_INFO(0x0275), }, /* Nokia X6 */
    { NOKIA_PCSUITE_ACM_INFO(0x026c), }, /* Nokia N97 Mini */
    { NOKIA_PCSUITE_ACM_INFO(0x0154), }, /* Nokia 5800 XpressMusic */
    { NOKIA_PCSUITE_ACM_INFO(0x04ce), }, /* Nokia E90 */
    { NOKIA_PCSUITE_ACM_INFO(0x01d4), }, /* Nokia E55 */
    { NOKIA_PCSUITE_ACM_INFO(0x0302), }, /* Nokia N8 */
    { NOKIA_PCSUITE_ACM_INFO(0x0335), }, /* Nokia E7 */
    { NOKIA_PCSUITE_ACM_INFO(0x03cd), }, /* Nokia C7 */
    { SAMSUNG_PCSUITE_ACM_INFO(0x6651), }, /* Samsung GTi8510 (INNOV8) */

    /* Support for Owen devices */
    { USB_DEVICE(0x03eb, 0x0030), }, /* Owen SI30 */

    /* NOTE: non-Nokia COMM/ACM/0xff is likely MSFT RNDIS... NOT a modem! */

    /* Support Lego NXT using pbLua firmware */
    { USB_DEVICE(0x0694, 0xff00),
    .driver_info = NOT_A_MODEM,
    },

    /* Support for Droids MuIn LCD */
    { USB_DEVICE(0x04d8, 0x000b),
    .driver_info = NO_DATA_INTERFACE,
    },

    /* control interfaces without any protocol set */
    { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
        USB_CDC_PROTO_NONE) },

    /* control interfaces with various AT-command sets */
    { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
        USB_CDC_ACM_PROTO_AT_V25TER) },
    { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
        USB_CDC_ACM_PROTO_AT_PCCA101) },
    { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
        USB_CDC_ACM_PROTO_AT_PCCA101_WAKE) },
    { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
        USB_CDC_ACM_PROTO_AT_GSM) },
    { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
        USB_CDC_ACM_PROTO_AT_3G) },
    { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
        USB_CDC_ACM_PROTO_AT_CDMA) },

    { }
};

MODULE_DEVICE_TABLE(usb, acm_ids);

static struct usb_driver acm_driver = {
    .name =     "cdc_acm",
    .probe =    acm_probe,
    .disconnect =   acm_disconnect,
#ifdef CONFIG_PM
    .suspend =  acm_suspend,
    .resume =   acm_resume,
    .reset_resume = acm_reset_resume,
#endif
    .id_table = acm_ids,
#ifdef CONFIG_PM
    .supports_autosuspend = 1,
#endif
    .disable_hub_initiated_lpm = 1,
};

/*
 * TTY driver structures.
 */

static const struct tty_operations acm_ops = {
    .install =      acm_tty_install,
    .open =         acm_tty_open,
    .close =        acm_tty_close,
    .cleanup =      acm_tty_cleanup,
    .hangup =       acm_tty_hangup,
    .write =        acm_tty_write,
    .write_room =       acm_tty_write_room,
    .ioctl =        acm_tty_ioctl,
    .throttle =     acm_tty_throttle,
    .unthrottle =       acm_tty_unthrottle,
    .chars_in_buffer =  acm_tty_chars_in_buffer,
    .break_ctl =        acm_tty_break_ctl,
    .set_termios =      acm_tty_set_termios,
    .tiocmget =     acm_tty_tiocmget,
    .tiocmset =     acm_tty_tiocmset,
};

/*
 * Init / exit.
 */

static int __init acm_init(void)
{
    int retval;
    acm_tty_driver = alloc_tty_driver(ACM_TTY_MINORS);
    if (!acm_tty_driver)
        return -ENOMEM;
    acm_tty_driver->driver_name = "acm",
    acm_tty_driver->name = "ttyACM",
    acm_tty_driver->major = ACM_TTY_MAJOR,
    acm_tty_driver->minor_start = 0,
    acm_tty_driver->type = TTY_DRIVER_TYPE_SERIAL,
    acm_tty_driver->subtype = SERIAL_TYPE_NORMAL,
    acm_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
    acm_tty_driver->init_termios = tty_std_termios;
    acm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD |
                                HUPCL | CLOCAL;
    tty_set_operations(acm_tty_driver, &acm_ops);

    retval = tty_register_driver(acm_tty_driver);
    if (retval) {
        put_tty_driver(acm_tty_driver);
        return retval;
    }

    retval = usb_register(&acm_driver);
    if (retval) {
        tty_unregister_driver(acm_tty_driver);
        put_tty_driver(acm_tty_driver);
        return retval;
    }

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

    return 0;
}

static void __exit acm_exit(void)
{
    usb_deregister(&acm_driver);
    tty_unregister_driver(acm_tty_driver);
    put_tty_driver(acm_tty_driver);
}

module_init(acm_init);
module_exit(acm_exit);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
MODULE_ALIAS_CHARDEV_MAJOR(ACM_TTY_MAJOR);