usb: vstusb.c : new driver for spectrometers used by Vernier Software & Technology, Inc.

This patch adds the vstusb driver to the drivers/usb/misc directory.
This driver provides support for Vernier Software & Technology
spectrometers, all made by Ocean Optics. The driver provides both IOCTL
and read()/write() methods for sending raw data to spectrometers across
the bulk channel. Each method allows for a configured timeout.

From: Stephen Ware <stephen.ware@eqware.net>
Signed-off-by: Dennis O'Brien <dennis.obrien@eqware.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 784 insertions, 0 deletions

diff --git a/drivers/usb/misc/Kconfig b/drivers/usb/misc/Kconfig
index 25e1157ab176..e463db5d8188 100644
--- a/drivers/usb/misc/Kconfig
+++ b/drivers/usb/misc/Kconfig
@@ -280,3 +280,18 @@ config USB_ISIGHTFW
           The firmware for this driver must be extracted from the MacOS
           driver beforehand. Tools for doing so are available at
           http://bersace03.free.fr
+
+config USB_VST
+        tristate "USB VST driver"
+        depends on USB
+        help
+          This driver is intended for Vernier Software Technologies
+          bulk usb devices such as their Ocean-Optics spectrometers or
+          Labquest.
+          It is a bulk channel driver with configurable read and write
+          timeouts.
+
+          To compile this driver as a module, choose M here: the
+          module will be called vstusb.
+
+
diff --git a/drivers/usb/misc/Makefile b/drivers/usb/misc/Makefile
index 39ce4a16b3d4..1334f7bdd7be 100644
--- a/drivers/usb/misc/Makefile
+++ b/drivers/usb/misc/Makefile
@@ -27,6 +27,7 @@ obj-$(CONFIG_USB_TEST)		+= usbtest.o
 obj-$(CONFIG_USB_TRANCEVIBRATOR)        += trancevibrator.o
 obj-$(CONFIG_USB_USS720)        += uss720.o
 obj-$(CONFIG_USB_SEVSEG)        += usbsevseg.o
+obj-$(CONFIG_USB_VST)           += vstusb.o
 
 obj-$(CONFIG_USB_SISUSBVGA)     += sisusbvga/
 
diff --git a/drivers/usb/misc/vstusb.c b/drivers/usb/misc/vstusb.c
new file mode 100644
index 000000000000..5ad75e4a0323
--- /dev/null
+++ b/drivers/usb/misc/vstusb.c
@@ -0,0 +1,768 @@
+/*****************************************************************************
+ *  File: drivers/usb/misc/vstusb.c
+ *
+ *  Purpose: Support for the bulk USB Vernier Spectrophotometers
+ *
+ *  Author:     Johnnie Peters
+ *              Axian Consulting
+ *              Beaverton, OR, USA 97005
+ *
+ *  Modified by:     EQware Engineering, Inc.
+ *                   Oregon City, OR, USA 97045
+ *
+ *  Copyright:  2007, 2008
+ *              Vernier Software & Technology
+ *              Beaverton, OR, USA 97005
+ *
+ *  Web:        www.vernier.com
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ *
+ *****************************************************************************/
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/uaccess.h>
+#include <linux/usb.h>
+
+#include <linux/usb/vstusb.h>
+
+#define DRIVER_VERSION "VST USB Driver Version 1.5"
+#define DRIVER_DESC "Vernier Software Technology Bulk USB Driver"
+
+#ifdef CONFIG_USB_DYNAMIC_MINORS
+        #define VSTUSB_MINOR_BASE       0
+#else
+        #define VSTUSB_MINOR_BASE       199
+#endif
+
+#define USB_VENDOR_OCEANOPTICS  0x2457
+#define USB_VENDOR_VERNIER      0x08F7  /* Vernier Software & Technology */
+
+#define USB_PRODUCT_USB2000     0x1002
+#define USB_PRODUCT_ADC1000_FW  0x1003  /* firmware download (renumerates) */
+#define USB_PRODUCT_ADC1000     0x1004
+#define USB_PRODUCT_HR2000_FW   0x1009  /* firmware download (renumerates) */
+#define USB_PRODUCT_HR2000      0x100A
+#define USB_PRODUCT_HR4000_FW   0x1011  /* firmware download (renumerates) */
+#define USB_PRODUCT_HR4000      0x1012
+#define USB_PRODUCT_USB650      0x1014  /* "Red Tide" */
+#define USB_PRODUCT_QE65000     0x1018
+#define USB_PRODUCT_USB4000     0x1022
+#define USB_PRODUCT_USB325      0x1024  /* "Vernier Spectrometer" */
+
+#define USB_PRODUCT_LABPRO      0x0001
+#define USB_PRODUCT_LABQUEST    0x0005
+
+static struct usb_device_id id_table[] = {
+        { USB_DEVICE(USB_VENDOR_OCEANOPTICS, USB_PRODUCT_USB2000)},
+        { USB_DEVICE(USB_VENDOR_OCEANOPTICS, USB_PRODUCT_HR4000)},
+        { USB_DEVICE(USB_VENDOR_OCEANOPTICS, USB_PRODUCT_USB650)},
+        { USB_DEVICE(USB_VENDOR_OCEANOPTICS, USB_PRODUCT_USB4000)},
+        { USB_DEVICE(USB_VENDOR_OCEANOPTICS, USB_PRODUCT_USB325)},
+        { USB_DEVICE(USB_VENDOR_VERNIER, USB_PRODUCT_LABQUEST)},
+        { USB_DEVICE(USB_VENDOR_VERNIER, USB_PRODUCT_LABPRO)},
+        {},
+};
+
+MODULE_DEVICE_TABLE(usb, id_table);
+
+struct vstusb_device {
+        struct mutex            lock;
+        struct usb_device       *usb_dev;
+        char                    present;
+        char                    isopen;
+        struct usb_anchor       submitted;
+        int                     rd_pipe;
+        int                     rd_timeout_ms;
+        int                     wr_pipe;
+        int                     wr_timeout_ms;
+};
+
+static struct usb_driver vstusb_driver;
+
+static int vstusb_open(struct inode *inode, struct file *file)
+{
+        struct vstusb_device *vstdev;
+        struct usb_interface *interface;
+
+        interface = usb_find_interface(&vstusb_driver, iminor(inode));
+
+        if (!interface) {
+                printk(KERN_ERR KBUILD_MODNAME
+                       ": %s - error, can't find device for minor %d\n",
+                       __func__, iminor(inode));
+                return -ENODEV;
+        }
+
+        vstdev = usb_get_intfdata(interface);
+
+        if (!vstdev)
+                return -ENODEV;
+
+        /* lock this device */
+        mutex_lock(&vstdev->lock);
+
+        /* can only open one time */
+        if ((!vstdev->present) || (vstdev->isopen)) {
+                mutex_unlock(&vstdev->lock);
+                return -EBUSY;
+        }
+
+        vstdev->isopen = 1;
+
+        /* save device in the file's private structure */
+        file->private_data = vstdev;
+
+        dev_dbg(&vstdev->usb_dev->dev, "%s: opened\n", __func__);
+
+        mutex_unlock(&vstdev->lock);
+
+        return 0;
+}
+
+static int vstusb_close(struct inode *inode, struct file *file)
+{
+        struct vstusb_device *vstdev;
+
+        vstdev = file->private_data;
+
+        if (vstdev == NULL)
+                return -ENODEV;
+
+        mutex_lock(&vstdev->lock);
+
+        vstdev->isopen = 0;
+        file->private_data = NULL;
+
+        /* if device is no longer present */
+        if (!vstdev->present) {
+                mutex_unlock(&vstdev->lock);
+                kfree(vstdev);
+        } else
+                mutex_unlock(&vstdev->lock);
+
+        return 0;
+}
+
+static void usb_api_blocking_completion(struct urb *urb)
+{
+        struct completion *completeit = urb->context;
+
+        complete(completeit);
+}
+
+static int vstusb_fill_and_send_urb(struct urb *urb,
+                                    struct usb_device *usb_dev,
+                                    unsigned int pipe, void *data,
+                                    unsigned int len, struct completion *done)
+{
+        struct usb_host_endpoint *ep;
+        struct usb_host_endpoint **hostep;
+        unsigned int pipend;
+
+        int status;
+
+        hostep = usb_pipein(pipe) ? usb_dev->ep_in : usb_dev->ep_out;
+        pipend = usb_pipeendpoint(pipe);
+        ep = hostep[pipend];
+
+        if (!ep || (len == 0))
+                return -EINVAL;
+
+        if ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
+            == USB_ENDPOINT_XFER_INT) {
+                pipe = (pipe & ~(3 << 30)) | (PIPE_INTERRUPT << 30);
+                usb_fill_int_urb(urb, usb_dev, pipe, data, len,
+                                 (usb_complete_t)usb_api_blocking_completion,
+                                 NULL, ep->desc.bInterval);
+        } else
+                usb_fill_bulk_urb(urb, usb_dev, pipe, data, len,
+                                  (usb_complete_t)usb_api_blocking_completion,
+                                  NULL);
+
+        init_completion(done);
+        urb->context = done;
+        urb->actual_length = 0;
+        status = usb_submit_urb(urb, GFP_KERNEL);
+
+        return status;
+}
+
+static int vstusb_complete_urb(struct urb *urb, struct completion *done,
+                               int timeout, int *actual_length)
+{
+        unsigned long expire;
+        int status;
+
+        expire = timeout ? msecs_to_jiffies(timeout) : MAX_SCHEDULE_TIMEOUT;
+        if (!wait_for_completion_interruptible_timeout(done, expire)) {
+                usb_kill_urb(urb);
+                status = urb->status == -ENOENT ? -ETIMEDOUT : urb->status;
+
+                dev_dbg(&urb->dev->dev,
+                        "%s timed out on ep%d%s len=%d/%d, urb status = %d\n",
+                        current->comm,
+                        usb_pipeendpoint(urb->pipe),
+                        usb_pipein(urb->pipe) ? "in" : "out",
+                        urb->actual_length,
+                        urb->transfer_buffer_length,
+                        urb->status);
+
+        } else {
+                if (signal_pending(current)) {
+                        /* if really an error */
+                        if (urb->status && !((urb->status == -ENOENT)     ||
+                                             (urb->status == -ECONNRESET) ||
+                                             (urb->status == -ESHUTDOWN))) {
+                                status = -EINTR;
+                                usb_kill_urb(urb);
+                        } else {
+                                status = 0;
+                        }
+
+                        dev_dbg(&urb->dev->dev,
+                                "%s: signal pending on ep%d%s len=%d/%d,"
+                                "urb status = %d\n",
+                                current->comm,
+                                usb_pipeendpoint(urb->pipe),
+                                usb_pipein(urb->pipe) ? "in" : "out",
+                                urb->actual_length,
+                                urb->transfer_buffer_length,
+                                urb->status);
+
+                } else {
+                        status = urb->status;
+                }
+        }
+
+        if (actual_length)
+                *actual_length = urb->actual_length;
+
+        return status;
+}
+
+static ssize_t vstusb_read(struct file *file, char __user *buffer,
+                           size_t count, loff_t *ppos)
+{
+        struct vstusb_device *vstdev;
+        int cnt = -1;
+        void *buf;
+        int retval = 0;
+
+        struct urb              *urb;
+        struct usb_device       *dev;
+        unsigned int            pipe;
+        int                     timeout;
+
+        DECLARE_COMPLETION_ONSTACK(done);
+
+        vstdev = file->private_data;
+
+        if (vstdev == NULL)
+                return -ENODEV;
+
+        /* verify that we actually want to read some data */
+        if (count == 0)
+                return -EINVAL;
+
+        /* lock this object */
+        if (mutex_lock_interruptible(&vstdev->lock))
+                return -ERESTARTSYS;
+
+        /* anyone home */
+        if (!vstdev->present) {
+                mutex_unlock(&vstdev->lock);
+                printk(KERN_ERR KBUILD_MODNAME
+                       ": %s: device not present\n", __func__);
+                return -ENODEV;
+        }
+
+        /* pull out the necessary data */
+        dev =     vstdev->usb_dev;
+        pipe =    usb_rcvbulkpipe(dev, vstdev->rd_pipe);
+        timeout = vstdev->rd_timeout_ms;
+
+        buf = kmalloc(count, GFP_KERNEL);
+        if (buf == NULL) {
+                mutex_unlock(&vstdev->lock);
+                return -ENOMEM;
+        }
+
+        urb = usb_alloc_urb(0, GFP_KERNEL);
+        if (!urb) {
+                kfree(buf);
+                mutex_unlock(&vstdev->lock);
+                return -ENOMEM;
+        }
+
+        usb_anchor_urb(urb, &vstdev->submitted);
+        retval = vstusb_fill_and_send_urb(urb, dev, pipe, buf, count, &done);
+        mutex_unlock(&vstdev->lock);
+        if (retval) {
+                usb_unanchor_urb(urb);
+                dev_err(&dev->dev, "%s: error %d filling and sending urb %d\n",
+                        __func__, retval, pipe);
+                goto exit;
+        }
+
+        retval = vstusb_complete_urb(urb, &done, timeout, &cnt);
+        if (retval) {
+                dev_err(&dev->dev, "%s: error %d completing urb %d\n",
+                        __func__, retval, pipe);
+                goto exit;
+        }
+
+        if (copy_to_user(buffer, buf, cnt)) {
+                dev_err(&dev->dev, "%s: can't copy_to_user\n", __func__);
+                retval = -EFAULT;
+        } else {
+                retval = cnt;
+                dev_dbg(&dev->dev, "%s: read %d bytes from pipe %d\n",
+                        __func__, cnt, pipe);
+        }
+
+exit:
+        usb_free_urb(urb);
+        kfree(buf);
+        return retval;
+}
+
+static ssize_t vstusb_write(struct file *file, const char __user *buffer,
+                            size_t count, loff_t *ppos)
+{
+        struct vstusb_device *vstdev;
+        int cnt = -1;
+        void *buf;
+        int retval = 0;
+
+        struct urb              *urb;
+        struct usb_device       *dev;
+        unsigned int            pipe;
+        int                     timeout;
+
+        DECLARE_COMPLETION_ONSTACK(done);
+
+        vstdev = file->private_data;
+
+        if (vstdev == NULL)
+                return -ENODEV;
+
+        /* verify that we actually have some data to write */
+        if (count == 0)
+                return retval;
+
+        /* lock this object */
+        if (mutex_lock_interruptible(&vstdev->lock))
+                return -ERESTARTSYS;
+
+        /* anyone home */
+        if (!vstdev->present) {
+                mutex_unlock(&vstdev->lock);
+                printk(KERN_ERR KBUILD_MODNAME
+                       ": %s: device not present\n", __func__);
+                return -ENODEV;
+        }
+
+        /* pull out the necessary data */
+        dev =     vstdev->usb_dev;
+        pipe =    usb_sndbulkpipe(dev, vstdev->wr_pipe);
+        timeout = vstdev->wr_timeout_ms;
+
+        buf = kmalloc(count, GFP_KERNEL);
+        if (buf == NULL) {
+                mutex_unlock(&vstdev->lock);
+                return -ENOMEM;
+        }
+
+        urb = usb_alloc_urb(0, GFP_KERNEL);
+        if (!urb) {
+                kfree(buf);
+                mutex_unlock(&vstdev->lock);
+                return -ENOMEM;
+        }
+
+        if (copy_from_user(buf, buffer, count)) {
+                dev_err(&dev->dev, "%s: can't copy_from_user\n", __func__);
+                retval = -EFAULT;
+                goto exit;
+        }
+
+        usb_anchor_urb(urb, &vstdev->submitted);
+        retval = vstusb_fill_and_send_urb(urb, dev, pipe, buf, count, &done);
+        mutex_unlock(&vstdev->lock);
+        if (retval) {
+                usb_unanchor_urb(urb);
+                dev_err(&dev->dev, "%s: error %d filling and sending urb %d\n",
+                        __func__, retval, pipe);
+                goto exit;
+        }
+
+        retval = vstusb_complete_urb(urb, &done, timeout, &cnt);
+        if (retval) {
+                dev_err(&dev->dev, "%s: error %d completing urb %d\n",
+                        __func__, retval, pipe);
+                goto exit;
+        } else {
+                retval = cnt;
+                dev_dbg(&dev->dev, "%s: sent %d bytes to pipe %d\n",
+                        __func__, cnt, pipe);
+        }
+
+exit:
+        usb_free_urb(urb);
+        kfree(buf);
+        return retval;
+}
+
+static long vstusb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+        int retval = 0;
+        int cnt = -1;
+        void __user *data = (void __user *)arg;
+        struct vstusb_args usb_data;
+
+        struct vstusb_device *vstdev;
+        void *buffer = NULL; /* must be initialized. buffer is
+                              * referenced on exit but not all
+                              * ioctls allocate it */
+
+        struct urb              *urb = NULL; /* must be initialized. urb is
+                                              * referenced on exit but not all
+                                              * ioctls allocate it */
+        struct usb_device       *dev;
+        unsigned int            pipe;
+        int                     timeout;
+
+        DECLARE_COMPLETION_ONSTACK(done);
+
+        vstdev = file->private_data;
+
+        if (_IOC_TYPE(cmd) != VST_IOC_MAGIC) {
+                dev_warn(&vstdev->usb_dev->dev,
+                         "%s: ioctl command %x, bad ioctl magic %x, "
+                         "expected %x\n", __func__, cmd,
+                         _IOC_TYPE(cmd), VST_IOC_MAGIC);
+                return -EINVAL;
+        }
+
+        if (vstdev == NULL)
+                return -ENODEV;
+
+        if (copy_from_user(&usb_data, data, sizeof(struct vstusb_args))) {
+                dev_err(&vstdev->usb_dev->dev, "%s: can't copy_from_user\n",
+                        __func__);
+                return -EFAULT;
+        }
+
+        /* lock this object */
+        if (mutex_lock_interruptible(&vstdev->lock)) {
+                retval = -ERESTARTSYS;
+                goto exit;
+        }
+
+        /* anyone home */
+        if (!vstdev->present) {
+                mutex_unlock(&vstdev->lock);
+                dev_err(&vstdev->usb_dev->dev, "%s: device not present\n",
+                        __func__);
+                retval = -ENODEV;
+                goto exit;
+        }
+
+        /* pull out the necessary data */
+        dev = vstdev->usb_dev;
+
+        switch (cmd) {
+
+        case IOCTL_VSTUSB_CONFIG_RW:
+
+                vstdev->rd_pipe = usb_data.rd_pipe;
+                vstdev->rd_timeout_ms = usb_data.rd_timeout_ms;
+                vstdev->wr_pipe = usb_data.wr_pipe;
+                vstdev->wr_timeout_ms = usb_data.wr_timeout_ms;
+
+                mutex_unlock(&vstdev->lock);
+
+                dev_dbg(&dev->dev, "%s: setting pipes/timeouts, "
+                        "rdpipe = %d, rdtimeout = %d, "
+                        "wrpipe = %d, wrtimeout = %d\n", __func__,
+                        vstdev->rd_pipe, vstdev->rd_timeout_ms,
+                        vstdev->wr_pipe, vstdev->wr_timeout_ms);
+                break;
+
+        case IOCTL_VSTUSB_SEND_PIPE:
+
+                if (usb_data.count == 0) {
+                        mutex_unlock(&vstdev->lock);
+                        retval = -EINVAL;
+                        goto exit;
+                }
+
+                buffer = kmalloc(usb_data.count, GFP_KERNEL);
+                if (buffer == NULL) {
+                        mutex_unlock(&vstdev->lock);
+                        retval = -ENOMEM;
+                        goto exit;
+                }
+
+                urb = usb_alloc_urb(0, GFP_KERNEL);
+                if (!urb) {
+                        mutex_unlock(&vstdev->lock);
+                        retval = -ENOMEM;
+                        goto exit;
+                }
+
+                timeout = usb_data.timeout_ms;
+
+                pipe = usb_sndbulkpipe(dev, usb_data.pipe);
+
+                if (copy_from_user(buffer, usb_data.buffer, usb_data.count)) {
+                        dev_err(&dev->dev, "%s: can't copy_from_user\n",
+                                __func__);
+                        mutex_unlock(&vstdev->lock);
+                        retval = -EFAULT;
+                        goto exit;
+                }
+
+                usb_anchor_urb(urb, &vstdev->submitted);
+                retval = vstusb_fill_and_send_urb(urb, dev, pipe, buffer,
+                                                  usb_data.count, &done);
+                mutex_unlock(&vstdev->lock);
+                if (retval) {
+                        usb_unanchor_urb(urb);
+                        dev_err(&dev->dev,
+                                "%s: error %d filling and sending urb %d\n",
+                                __func__, retval, pipe);
+                        goto exit;
+                }
+
+                retval = vstusb_complete_urb(urb, &done, timeout, &cnt);
+                if (retval) {
+                        dev_err(&dev->dev, "%s: error %d completing urb %d\n",
+                                __func__, retval, pipe);
+                }
+
+                break;
+        case IOCTL_VSTUSB_RECV_PIPE:
+
+                if (usb_data.count == 0) {
+                        mutex_unlock(&vstdev->lock);
+                        retval = -EINVAL;
+                        goto exit;
+                }
+
+                buffer = kmalloc(usb_data.count, GFP_KERNEL);
+                if (buffer == NULL) {
+                        mutex_unlock(&vstdev->lock);
+                        retval = -ENOMEM;
+                        goto exit;
+                }
+
+                urb = usb_alloc_urb(0, GFP_KERNEL);
+                if (!urb) {
+                        mutex_unlock(&vstdev->lock);
+                        retval = -ENOMEM;
+                        goto exit;
+                }
+
+                timeout = usb_data.timeout_ms;
+
+                pipe = usb_rcvbulkpipe(dev, usb_data.pipe);
+
+                usb_anchor_urb(urb, &vstdev->submitted);
+                retval = vstusb_fill_and_send_urb(urb, dev, pipe, buffer,
+                                                  usb_data.count, &done);
+                mutex_unlock(&vstdev->lock);
+                if (retval) {
+                        usb_unanchor_urb(urb);
+                        dev_err(&dev->dev,
+                                "%s: error %d filling and sending urb %d\n",
+                                __func__, retval, pipe);
+                        goto exit;
+                }
+
+                retval = vstusb_complete_urb(urb, &done, timeout, &cnt);
+                if (retval) {
+                        dev_err(&dev->dev, "%s: error %d completing urb %d\n",
+                                __func__, retval, pipe);
+                        goto exit;
+                }
+
+                if (copy_to_user(usb_data.buffer, buffer, cnt)) {
+                        dev_err(&dev->dev, "%s: can't copy_to_user\n",
+                                __func__);
+                        retval = -EFAULT;
+                        goto exit;
+                }
+
+                usb_data.count = cnt;
+                if (copy_to_user(data, &usb_data, sizeof(struct vstusb_args))) {
+                        dev_err(&dev->dev, "%s: can't copy_to_user\n",
+                                __func__);
+                        retval = -EFAULT;
+                } else {
+                        dev_dbg(&dev->dev, "%s: recv %d bytes from pipe %d\n",
+                                __func__, usb_data.count, usb_data.pipe);
+                }
+
+                break;
+
+        default:
+                mutex_unlock(&vstdev->lock);
+                dev_warn(&dev->dev, "ioctl_vstusb: invalid ioctl cmd %x\n",
+                         cmd);
+                return -EINVAL;
+                break;
+        }
+exit:
+        usb_free_urb(urb);
+        kfree(buffer);
+        return retval;
+}
+
+static const struct file_operations vstusb_fops = {
+        .owner =                THIS_MODULE,
+        .read =                 vstusb_read,
+        .write =                vstusb_write,
+        .unlocked_ioctl =       vstusb_ioctl,
+        .compat_ioctl =         vstusb_ioctl,
+        .open =                 vstusb_open,
+        .release =              vstusb_close,
+};
+
+static struct usb_class_driver usb_vstusb_class = {
+        .name =         "usb/vstusb%d",
+        .fops =         &vstusb_fops,
+        .minor_base =   VSTUSB_MINOR_BASE,
+};
+
+static int vstusb_probe(struct usb_interface *intf,
+                        const struct usb_device_id *id)
+{
+        struct usb_device *dev = interface_to_usbdev(intf);
+        struct vstusb_device *vstdev;
+        int i;
+        int retval = 0;
+
+        /* allocate memory for our device state and intialize it */
+
+        vstdev = kzalloc(sizeof(*vstdev), GFP_KERNEL);
+        if (vstdev == NULL)
+                return -ENOMEM;
+
+        mutex_init(&vstdev->lock);
+
+        i = dev->descriptor.bcdDevice;
+
+        dev_dbg(&intf->dev, "Version %1d%1d.%1d%1d found at address %d\n",
+                (i & 0xF000) >> 12, (i & 0xF00) >> 8,
+                (i & 0xF0) >> 4, (i & 0xF), dev->devnum);
+
+        vstdev->present = 1;
+        vstdev->isopen = 0;
+        vstdev->usb_dev = dev;
+        init_usb_anchor(&vstdev->submitted);
+
+        usb_set_intfdata(intf, vstdev);
+        retval = usb_register_dev(intf, &usb_vstusb_class);
+        if (retval) {
+                dev_err(&intf->dev,
+                        "%s: Not able to get a minor for this device.\n",
+                        __func__);
+                usb_set_intfdata(intf, NULL);
+                kfree(vstdev);
+                return retval;
+        }
+
+        /* let the user know what node this device is now attached to */
+        dev_info(&intf->dev,
+                 "VST USB Device #%d now attached to major %d minor %d\n",
+                 (intf->minor - VSTUSB_MINOR_BASE), USB_MAJOR, intf->minor);
+
+        dev_info(&intf->dev, "%s, %s\n", DRIVER_DESC, DRIVER_VERSION);
+
+        return retval;
+}
+
+static void vstusb_disconnect(struct usb_interface *intf)
+{
+        struct vstusb_device *vstdev = usb_get_intfdata(intf);
+
+        usb_deregister_dev(intf, &usb_vstusb_class);
+        usb_set_intfdata(intf, NULL);
+
+        if (vstdev) {
+
+                mutex_lock(&vstdev->lock);
+                vstdev->present = 0;
+
+                usb_kill_anchored_urbs(&vstdev->submitted);
+
+                /* if the device is not opened, then we clean up right now */
+                if (!vstdev->isopen) {
+                        mutex_unlock(&vstdev->lock);
+                        kfree(vstdev);
+                } else
+                        mutex_unlock(&vstdev->lock);
+
+        }
+}
+
+static int vstusb_suspend(struct usb_interface *intf, pm_message_t message)
+{
+        struct vstusb_device *vstdev = usb_get_intfdata(intf);
+        int time;
+        if (!vstdev)
+                return 0;
+
+        mutex_lock(&vstdev->lock);
+        time = usb_wait_anchor_empty_timeout(&vstdev->submitted, 1000);
+        if (!time)
+                usb_kill_anchored_urbs(&vstdev->submitted);
+        mutex_unlock(&vstdev->lock);
+
+        return 0;
+}
+
+static int vstusb_resume(struct usb_interface *intf)
+{
+        return 0;
+}
+
+static struct usb_driver vstusb_driver = {
+        .name =         "vstusb",
+        .probe =        vstusb_probe,
+        .disconnect =   vstusb_disconnect,
+        .suspend =      vstusb_suspend,
+        .resume =       vstusb_resume,
+        .id_table = id_table,
+};
+
+static int __init vstusb_init(void)
+{
+        int rc;
+
+        rc = usb_register(&vstusb_driver);
+        if (rc)
+                printk(KERN_ERR "%s: failed to register (%d)", __func__, rc);
+
+        return rc;
+}
+
+static void __exit vstusb_exit(void)
+{
+        usb_deregister(&vstusb_driver);
+}
+
+module_init(vstusb_init);
+module_exit(vstusb_exit);
+
+MODULE_AUTHOR("Dennis O'Brien/Stephen Ware");
+MODULE_DESCRIPTION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");