Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / usb / class / cdc-acm.c
diff --git a/kernel/drivers/usb/class/cdc-acm.c b/kernel/drivers/usb/class/cdc-acm.c
new file mode 100644 (file)
index 0000000..a086e1d
--- /dev/null
@@ -0,0 +1,1965 @@
+/*
+ * cdc-acm.c
+ *
+ * Copyright (c) 1999 Armin Fuerst     <fuerst@in.tum.de>
+ * Copyright (c) 1999 Pavel Machek     <pavel@ucw.cz>
+ * Copyright (c) 1999 Johannes Erdfelt <johannes@erdfelt.com>
+ * Copyright (c) 2000 Vojtech Pavlik   <vojtech@suse.cz>
+ * Copyright (c) 2004 Oliver Neukum    <oliver@neukum.name>
+ * Copyright (c) 2005 David Kubicek    <dave@awk.cz>
+ * Copyright (c) 2011 Johan Hovold     <jhovold@gmail.com>
+ *
+ * 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);
+
+static void acm_tty_set_termios(struct tty_struct *tty,
+                               struct ktermios *termios_old);
+
+/*
+ * 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;
+
+       retval = usb_autopm_get_interface(acm->control);
+       if (retval)
+               return retval;
+
+       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);
+
+       usb_autopm_put_interface(acm->control);
+
+       return retval < 0 ? retval : 0;
+}
+
+/* devices aren't required to support these requests.
+ * the cdc acm descriptor tells whether they do...
+ */
+static inline int acm_set_control(struct acm *acm, int control)
+{
+       if (acm->quirks & QUIRK_CONTROL_LINE_STATE)
+               return -EOPNOTSUPP;
+
+       return 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;
+}
+
+/*
+ * 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;
+       unsigned char *data;
+       int newctrl;
+       int difference;
+       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:
+               newctrl = get_unaligned_le16(data);
+
+               if (!acm->clocal && (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
+                       dev_dbg(&acm->control->dev, "%s - calling hangup\n",
+                                       __func__);
+                       tty_port_tty_hangup(&acm->port, false);
+               }
+
+               difference = acm->ctrlin ^ newctrl;
+               spin_lock(&acm->read_lock);
+               acm->ctrlin = newctrl;
+               acm->oldcount = acm->iocount;
+
+               if (difference & ACM_CTRL_DSR)
+                       acm->iocount.dsr++;
+               if (difference & ACM_CTRL_BRK)
+                       acm->iocount.brk++;
+               if (difference & ACM_CTRL_RI)
+                       acm->iocount.rng++;
+               if (difference & ACM_CTRL_DCD)
+                       acm->iocount.dcd++;
+               if (difference & ACM_CTRL_FRAMING)
+                       acm->iocount.frame++;
+               if (difference & ACM_CTRL_PARITY)
+                       acm->iocount.parity++;
+               if (difference & ACM_CTRL_OVERRUN)
+                       acm->iocount.overrun++;
+               spin_unlock(&acm->read_lock);
+
+               if (difference)
+                       wake_up_all(&acm->wioctl);
+
+               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 && retval != -EPERM)
+               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)
+{
+       if (!urb->actual_length)
+               return;
+
+       tty_insert_flip_string(&acm->port, urb->transfer_buffer,
+                       urb->actual_length);
+       tty_flip_buffer_push(&acm->port);
+}
+
+static void acm_read_bulk_callback(struct urb *urb)
+{
+       struct acm_rb *rb = urb->context;
+       struct acm *acm = rb->instance;
+       unsigned long flags;
+       int status = urb->status;
+
+       dev_vdbg(&acm->data->dev, "%s - urb %d, len %d\n", __func__,
+                                       rb->index, urb->actual_length);
+
+       if (!acm->dev) {
+               set_bit(rb->index, &acm->read_urbs_free);
+               dev_dbg(&acm->data->dev, "%s - disconnected\n", __func__);
+               return;
+       }
+
+       if (status) {
+               set_bit(rb->index, &acm->read_urbs_free);
+               dev_dbg(&acm->data->dev, "%s - non-zero urb status: %d\n",
+                                                       __func__, status);
+               return;
+       }
+
+       usb_mark_last_busy(acm->dev);
+
+       acm_process_read_urb(acm, urb);
+       /*
+        * Unthrottle may run on another CPU which needs to see events
+        * in the same order. Submission has an implict barrier
+        */
+       smp_mb__before_atomic();
+       set_bit(rb->index, &acm->read_urbs_free);
+
+       /* throttle device if requested by tty */
+       spin_lock_irqsave(&acm->read_lock, flags);
+       acm->throttled = acm->throttle_req;
+       if (!acm->throttled) {
+               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;
+       int status = urb->status;
+
+       if (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,
+                       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);
+
+       dev_vdbg(&acm->data->dev, "%s\n", __func__);
+
+       tty_port_tty_wakeup(&acm->port);
+}
+
+/*
+ * 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 void acm_port_dtr_rts(struct tty_port *port, int raise)
+{
+       struct acm *acm = container_of(port, struct acm, port);
+       int val;
+       int res;
+
+       if (raise)
+               val = ACM_CTRL_DTR | ACM_CTRL_RTS;
+       else
+               val = 0;
+
+       /* FIXME: add missing ctrlout locking throughout driver */
+       acm->ctrlout = val;
+
+       res = acm_set_control(acm, val);
+       if (res && (acm->ctrl_caps & USB_CDC_CAP_LINE))
+               dev_err(&acm->control->dev, "failed to set dtr/rts\n");
+}
+
+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;
+       int i;
+
+       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;
+       retval = usb_submit_urb(acm->ctrlurb, GFP_KERNEL);
+       if (retval) {
+               dev_err(&acm->control->dev,
+                       "%s - usb_submit_urb(ctrl irq) failed\n", __func__);
+               goto error_submit_urb;
+       }
+
+       acm_tty_set_termios(tty, NULL);
+
+       /*
+        * 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);
+
+       retval = acm_submit_read_urbs(acm, GFP_KERNEL);
+       if (retval)
+               goto error_submit_read_urbs;
+
+       usb_autopm_put_interface(acm->control);
+
+       mutex_unlock(&acm->mutex);
+
+       return 0;
+
+error_submit_read_urbs:
+       for (i = 0; i < acm->rx_buflimit; i++)
+               usb_kill_urb(acm->read_urbs[i]);
+       usb_kill_urb(acm->ctrlurb);
+error_submit_urb:
+       usb_autopm_put_interface(acm->control);
+error_get_interface:
+disconnected:
+       mutex_unlock(&acm->mutex);
+
+       return usb_translate_errors(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__);
+
+       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);
+       struct urb *urb;
+       struct acm_wb *wb;
+       int i;
+
+       dev_dbg(&acm->control->dev, "%s\n", __func__);
+
+       /*
+        * Need to grab write_lock to prevent race with resume, but no need to
+        * hold it due to the tty-port initialised flag.
+        */
+       spin_lock_irq(&acm->write_lock);
+       spin_unlock_irq(&acm->write_lock);
+
+       usb_autopm_get_interface_no_resume(acm->control);
+       acm->control->needs_remote_wakeup = 0;
+       usb_autopm_put_interface(acm->control);
+
+       for (;;) {
+               urb = usb_get_from_anchor(&acm->delayed);
+               if (!urb)
+                       break;
+               wb = urb->context;
+               wb->use = 0;
+               usb_autopm_put_interface_async(acm->control);
+       }
+
+       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]);
+}
+
+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];
+
+       if (!acm->dev) {
+               wb->use = 0;
+               spin_unlock_irqrestore(&acm->write_lock, flags);
+               return -ENODEV;
+       }
+
+       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;
+
+       stat = usb_autopm_get_interface_async(acm->control);
+       if (stat) {
+               wb->use = 0;
+               spin_unlock_irqrestore(&acm->write_lock, flags);
+               return stat;
+       }
+
+       if (acm->susp_count) {
+               usb_anchor_urb(wb->urb, &acm->delayed);
+               spin_unlock_irqrestore(&acm->write_lock, flags);
+               return count;
+       }
+
+       stat = acm_start_wb(acm, wb);
+       spin_unlock_irqrestore(&acm->write_lock, flags);
+
+       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 wait_serial_change(struct acm *acm, unsigned long arg)
+{
+       int rv = 0;
+       DECLARE_WAITQUEUE(wait, current);
+       struct async_icount old, new;
+
+       if (arg & (TIOCM_DSR | TIOCM_RI | TIOCM_CD ))
+               return -EINVAL;
+       do {
+               spin_lock_irq(&acm->read_lock);
+               old = acm->oldcount;
+               new = acm->iocount;
+               acm->oldcount = new;
+               spin_unlock_irq(&acm->read_lock);
+
+               if ((arg & TIOCM_DSR) &&
+                       old.dsr != new.dsr)
+                       break;
+               if ((arg & TIOCM_CD)  &&
+                       old.dcd != new.dcd)
+                       break;
+               if ((arg & TIOCM_RI) &&
+                       old.rng != new.rng)
+                       break;
+
+               add_wait_queue(&acm->wioctl, &wait);
+               set_current_state(TASK_INTERRUPTIBLE);
+               schedule();
+               remove_wait_queue(&acm->wioctl, &wait);
+               if (acm->disconnected) {
+                       if (arg & TIOCM_CD)
+                               break;
+                       else
+                               rv = -ENODEV;
+               } else {
+                       if (signal_pending(current))
+                               rv = -ERESTARTSYS;
+               }
+       } while (!rv);
+
+       
+
+       return rv;
+}
+
+static int get_serial_usage(struct acm *acm,
+                           struct serial_icounter_struct __user *count)
+{
+       struct serial_icounter_struct icount;
+       int rv = 0;
+
+       memset(&icount, 0, sizeof(icount));
+       icount.dsr = acm->iocount.dsr;
+       icount.rng = acm->iocount.rng;
+       icount.dcd = acm->iocount.dcd;
+       icount.frame = acm->iocount.frame;
+       icount.overrun = acm->iocount.overrun;
+       icount.parity = acm->iocount.parity;
+       icount.brk = acm->iocount.brk;
+
+       if (copy_to_user(count, &icount, sizeof(icount)) > 0)
+               rv = -EFAULT;
+
+       return rv;
+}
+
+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;
+       case TIOCMIWAIT:
+               rv = usb_autopm_get_interface(acm->control);
+               if (rv < 0) {
+                       rv = -EIO;
+                       break;
+               }
+               rv = wait_serial_change(acm, arg);
+               usb_autopm_put_interface(acm->control);
+               break;
+       case TIOCGICOUNT:
+               rv = get_serial_usage(acm, (struct serial_icounter_struct __user *) arg);
+               break;
+       }
+
+       return rv;
+}
+
+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 (C_BAUD(tty) == B0) {
+               newline.dwDTERate = acm->line.dwDTERate;
+               newctrl &= ~ACM_CTRL_DTR;
+       } else if (termios_old && (termios_old->c_cflag & CBAUD) == B0) {
+               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 = {
+       .dtr_rts = acm_port_dtr_rts,
+       .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;
+       unsigned int elength = 0;
+       int combined_interfaces = 0;
+       struct device *tty_dev;
+       int rv = -ENOMEM;
+
+       /* normal quirks */
+       quirks = (unsigned long)id->driver_info;
+
+       if (quirks == IGNORE_DEVICE)
+               return -ENODEV;
+
+       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) {
+               elength = buffer[0];
+               if (!elength) {
+                       dev_err(&intf->dev, "skipping garbage byte\n");
+                       elength = 1;
+                       goto next_desc;
+               }
+               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 (elength < sizeof(struct usb_cdc_union_desc))
+                               goto next_desc;
+                       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*/
+                       if (elength < sizeof(struct usb_cdc_country_functional_desc))
+                               goto next_desc;
+                       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:
+                       if (elength < 4)
+                               goto next_desc;
+                       ac_management_function = buffer[3];
+                       break;
+               case USB_CDC_CALL_MANAGEMENT_TYPE:
+                       if (elength < 5)
+                               goto next_desc;
+                       call_management_function = buffer[3];
+                       call_interface_num = buffer[4];
+                       break;
+               default:
+                       /*
+                        * there are LOTS more CDC descriptors that
+                        * could legitimately be found here.
+                        */
+                       dev_dbg(&intf->dev, "Ignoring descriptor: "
+                                       "type %02x, length %ud\n",
+                                       buffer[2], elength);
+                       break;
+               }
+next_desc:
+               buflen -= elength;
+               buffer += elength;
+       }
+
+       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)
+               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);
+       init_waitqueue_head(&acm->wioctl);
+       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;
+       init_usb_anchor(&acm->delayed);
+       acm->quirks = quirks;
+
+       buf = usb_alloc_coherent(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
+       if (!buf)
+               goto alloc_fail2;
+       acm->ctrl_buffer = buf;
+
+       if (acm_write_buffers_alloc(acm) < 0)
+               goto alloc_fail4;
+
+       acm->ctrlurb = usb_alloc_urb(0, GFP_KERNEL);
+       if (!acm->ctrlurb)
+               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)
+                       goto alloc_fail6;
+               rb->index = i;
+               rb->instance = acm;
+
+               urb = usb_alloc_urb(0, GFP_KERNEL);
+               if (!urb)
+                       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)
+                       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 : 16);
+       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->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_dev = tty_port_register_device(&acm->port, acm_tty_driver, minor,
+                       &control_interface->dev);
+       if (IS_ERR(tty_dev)) {
+               rv = PTR_ERR(tty_dev);
+               goto alloc_fail8;
+       }
+
+       if (quirks & CLEAR_HALT_CONDITIONS) {
+               usb_clear_halt(usb_dev, usb_rcvbulkpipe(usb_dev, epread->bEndpointAddress));
+               usb_clear_halt(usb_dev, usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress));
+       }
+
+       return 0;
+alloc_fail8:
+       if (acm->country_codes) {
+               device_remove_file(&acm->control->dev,
+                               &dev_attr_wCountryCodes);
+               device_remove_file(&acm->control->dev,
+                               &dev_attr_iCountryCodeRelDate);
+               kfree(acm->country_codes);
+       }
+       device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
+alloc_fail7:
+       usb_set_intfdata(intf, NULL);
+       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 rv;
+}
+
+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);
+       }
+       wake_up_all(&acm->wioctl);
+       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);
+
+       tty_unregister_device(acm_tty_driver, acm->minor);
+
+       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;
+
+       spin_lock_irq(&acm->write_lock);
+       if (PMSG_IS_AUTO(message)) {
+               if (acm->transmitting) {
+                       spin_unlock_irq(&acm->write_lock);
+                       return -EBUSY;
+               }
+       }
+       cnt = acm->susp_count++;
+       spin_unlock_irq(&acm->write_lock);
+
+       if (cnt)
+               return 0;
+
+       stop_data_traffic(acm);
+
+       return 0;
+}
+
+static int acm_resume(struct usb_interface *intf)
+{
+       struct acm *acm = usb_get_intfdata(intf);
+       struct urb *urb;
+       int rv = 0;
+
+       spin_lock_irq(&acm->write_lock);
+
+       if (--acm->susp_count)
+               goto out;
+
+       if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) {
+               rv = usb_submit_urb(acm->ctrlurb, GFP_ATOMIC);
+
+               for (;;) {
+                       urb = usb_get_from_anchor(&acm->delayed);
+                       if (!urb)
+                               break;
+
+                       acm_start_wb(acm, urb->context);
+               }
+
+               /*
+                * delayed error checking because we must
+                * do the write path at all cost
+                */
+               if (rv < 0)
+                       goto out;
+
+               rv = acm_submit_read_urbs(acm, GFP_ATOMIC);
+       }
+out:
+       spin_unlock_irq(&acm->write_lock);
+
+       return rv;
+}
+
+static int acm_reset_resume(struct usb_interface *intf)
+{
+       struct acm *acm = usb_get_intfdata(intf);
+
+       if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags))
+               tty_port_tty_hangup(&acm->port, false);
+
+       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(0x076d, 0x0006), /* Denso Cradle CU-321 */
+       .driver_info = NO_UNION_NORMAL, },/* has no union descriptor */
+       { USB_DEVICE(0x17ef, 0x7000), /* Lenovo USB modem */
+       .driver_info = NO_UNION_NORMAL, },/* has no union descriptor */
+       { USB_DEVICE(0x0870, 0x0001), /* Metricom GS Modem */
+       .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
+       },
+       { USB_DEVICE(0x0e8d, 0x0003), /* FIREFLY, MediaTek Inc; andrey.arapov@gmail.com */
+       .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(0x20df, 0x0001), /* Simtec Electronics Entropy Key */
+       .driver_info = QUIRK_CONTROL_LINE_STATE, },
+       { USB_DEVICE(0x2184, 0x001c) }, /* GW Instek AFG-2225 */
+       { USB_DEVICE(0x22b8, 0x6425), /* Motorola MOTOMAGX phones */
+       },
+       /* Motorola H24 HSPA module: */
+       { USB_DEVICE(0x22b8, 0x2d91) }, /* modem                                */
+       { USB_DEVICE(0x22b8, 0x2d92),   /* modem           + diagnostics        */
+       .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+       },
+       { USB_DEVICE(0x22b8, 0x2d93),   /* modem + AT port                      */
+       .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+       },
+       { USB_DEVICE(0x22b8, 0x2d95),   /* modem + AT port + diagnostics        */
+       .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+       },
+       { USB_DEVICE(0x22b8, 0x2d96),   /* modem                         + NMEA */
+       .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+       },
+       { USB_DEVICE(0x22b8, 0x2d97),   /* modem           + diagnostics + NMEA */
+       .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+       },
+       { USB_DEVICE(0x22b8, 0x2d99),   /* modem + AT port               + NMEA */
+       .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+       },
+       { USB_DEVICE(0x22b8, 0x2d9a),   /* modem + AT port + diagnostics + NMEA */
+       .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+       },
+
+       { 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(0x05f9, 0x4002), /* PSC Scanning, Magellan 800i */
+       .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 */
+       },
+
+       { USB_DEVICE(0x2912, 0x0001), /* ATOL FPrint */
+       .driver_info = CLEAR_HALT_CONDITIONS,
+       },
+
+       /* 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 for Droids MuIn LCD */
+       { USB_DEVICE(0x04d8, 0x000b),
+       .driver_info = NO_DATA_INTERFACE,
+       },
+
+#if IS_ENABLED(CONFIG_INPUT_IMS_PCU)
+       { USB_DEVICE(0x04d8, 0x0082),   /* Application mode */
+       .driver_info = IGNORE_DEVICE,
+       },
+       { USB_DEVICE(0x04d8, 0x0083),   /* Bootloader mode */
+       .driver_info = IGNORE_DEVICE,
+       },
+#endif
+
+       /* 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);