2 files changed, 289 insertions, 148 deletions

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 9543b19d410c..b32ccb461019 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -39,6 +39,7 @@
 #include <linux/serial.h>
 #include <linux/tty_driver.h>
 #include <linux/tty_flip.h>
+#include <linux/serial.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/uaccess.h>
@@ -508,17 +509,12 @@ static int acm_tty_install(struct tty_driver *driver, struct tty_struct *tty)
         if (!acm)
                 return -ENODEV;
 
-        retval = tty_init_termios(tty);
+        retval = tty_standard_install(driver, tty);
         if (retval)
                 goto error_init_termios;
 
         tty->driver_data = acm;
 
-        /* Final install (we use the default method) */
-        tty_driver_kref_get(driver);
-        tty->count++;
-        driver->ttys[tty->index] = tty;
-
         return 0;
 
 error_init_termios:
@@ -773,10 +769,37 @@ static int acm_tty_tiocmset(struct tty_struct *tty,
         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);
+
+        if (copy_to_user(info, &tmp, sizeof(tmp)))
+                return -EFAULT;
+        else
+                return 0;
+}
+
 static int acm_tty_ioctl(struct tty_struct *tty,
                                         unsigned int cmd, unsigned long arg)
 {
-        return -ENOIOCTLCMD;
+        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;
+        }
+
+        return rv;
 }
 
 static const __u32 acm_tty_speed[] = {
@@ -1675,7 +1698,6 @@ static int __init acm_init(void)
         acm_tty_driver = alloc_tty_driver(ACM_TTY_MINORS);
         if (!acm_tty_driver)
                 return -ENOMEM;
-        acm_tty_driver->owner = THIS_MODULE,
         acm_tty_driver->driver_name = "acm",
         acm_tty_driver->name = "ttyACM",
         acm_tty_driver->major = ACM_TTY_MAJOR,
diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c
index 1c50baff7725..c6f6560d436c 100644
--- a/drivers/usb/class/cdc-wdm.c
+++ b/drivers/usb/class/cdc-wdm.c
@@ -23,6 +23,7 @@
 #include <linux/usb/cdc.h>
 #include <asm/byteorder.h>
 #include <asm/unaligned.h>
+#include <linux/usb/cdc-wdm.h>
 
 /*
  * Version Information
@@ -31,6 +32,8 @@
 #define DRIVER_AUTHOR "Oliver Neukum"
 #define DRIVER_DESC "USB Abstract Control Model driver for USB WCM Device Management"
 
+#define HUAWEI_VENDOR_ID        0x12D1
+
 static const struct usb_device_id wdm_ids[] = {
         {
                 .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS |
@@ -38,6 +41,20 @@ static const struct usb_device_id wdm_ids[] = {
                 .bInterfaceClass = USB_CLASS_COMM,
                 .bInterfaceSubClass = USB_CDC_SUBCLASS_DMM
         },
+        {
+                /* 
+                 * Huawei E392, E398 and possibly other Qualcomm based modems
+                 * embed the Qualcomm QMI protocol inside CDC on CDC ECM like
+                 * control interfaces.  Userspace access to this is required
+                 * to configure the accompanying data interface
+                 */
+                .match_flags        = USB_DEVICE_ID_MATCH_VENDOR |
+                                        USB_DEVICE_ID_MATCH_INT_INFO,
+                .idVendor           = HUAWEI_VENDOR_ID,
+                .bInterfaceClass    = USB_CLASS_VENDOR_SPEC,
+                .bInterfaceSubClass = 1,
+                .bInterfaceProtocol = 9, /* NOTE: CDC ECM control interface! */
+        },
         { }
 };
 
@@ -54,11 +71,16 @@ MODULE_DEVICE_TABLE (usb, wdm_ids);
 #define WDM_POLL_RUNNING        6
 #define WDM_RESPONDING          7
 #define WDM_SUSPENDING          8
+#define WDM_RESETTING           9
 
 #define WDM_MAX                 16
 
+/* CDC-WMC r1.1 requires wMaxCommand to be "at least 256 decimal (0x100)" */
+#define WDM_DEFAULT_BUFSIZE     256
 
 static DEFINE_MUTEX(wdm_mutex);
+static DEFINE_SPINLOCK(wdm_device_list_lock);
+static LIST_HEAD(wdm_device_list);
 
 /* --- method tables --- */
 
@@ -80,7 +102,6 @@ struct wdm_device {
         u16                     bufsize;
         u16                     wMaxCommand;
         u16                     wMaxPacketSize;
-        u16                     bMaxPacketSize0;
         __le16                  inum;
         int                     reslength;
         int                     length;
@@ -88,15 +109,46 @@ struct wdm_device {
         int                     count;
         dma_addr_t              shandle;
         dma_addr_t              ihandle;
-        struct mutex            lock;
+        struct mutex            wlock;
+        struct mutex            rlock;
         wait_queue_head_t       wait;
         struct work_struct      rxwork;
         int                     werr;
         int                     rerr;
+
+        struct list_head        device_list;
+        int                     (*manage_power)(struct usb_interface *, int);
 };
 
 static struct usb_driver wdm_driver;
 
+/* return intfdata if we own the interface, else look up intf in the list */
+static struct wdm_device *wdm_find_device(struct usb_interface *intf)
+{
+        struct wdm_device *desc = NULL;
+
+        spin_lock(&wdm_device_list_lock);
+        list_for_each_entry(desc, &wdm_device_list, device_list)
+                if (desc->intf == intf)
+                        break;
+        spin_unlock(&wdm_device_list_lock);
+
+        return desc;
+}
+
+static struct wdm_device *wdm_find_device_by_minor(int minor)
+{
+        struct wdm_device *desc = NULL;
+
+        spin_lock(&wdm_device_list_lock);
+        list_for_each_entry(desc, &wdm_device_list, device_list)
+                if (desc->intf->minor == minor)
+                        break;
+        spin_unlock(&wdm_device_list_lock);
+
+        return desc;
+}
+
 /* --- callbacks --- */
 static void wdm_out_callback(struct urb *urb)
 {
@@ -159,11 +211,9 @@ static void wdm_int_callback(struct urb *urb)
         int rv = 0;
         int status = urb->status;
         struct wdm_device *desc;
-        struct usb_ctrlrequest *req;
         struct usb_cdc_notification *dr;
 
         desc = urb->context;
-        req = desc->irq;
         dr = (struct usb_cdc_notification *)desc->sbuf;
 
         if (status) {
@@ -210,24 +260,6 @@ static void wdm_int_callback(struct urb *urb)
                 goto exit;
         }
 
-        req->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE);
-        req->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE;
-        req->wValue = 0;
-        req->wIndex = desc->inum;
-        req->wLength = cpu_to_le16(desc->wMaxCommand);
-
-        usb_fill_control_urb(
-                desc->response,
-                interface_to_usbdev(desc->intf),
-                /* using common endpoint 0 */
-                usb_rcvctrlpipe(interface_to_usbdev(desc->intf), 0),
-                (unsigned char *)req,
-                desc->inbuf,
-                desc->wMaxCommand,
-                wdm_in_callback,
-                desc
-        );
-        desc->response->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
         spin_lock(&desc->iuspin);
         clear_bit(WDM_READ, &desc->flags);
         set_bit(WDM_RESPONDING, &desc->flags);
@@ -276,14 +308,11 @@ static void free_urbs(struct wdm_device *desc)
 
 static void cleanup(struct wdm_device *desc)
 {
-        usb_free_coherent(interface_to_usbdev(desc->intf),
-                          desc->wMaxPacketSize,
-                          desc->sbuf,
-                          desc->validity->transfer_dma);
-        usb_free_coherent(interface_to_usbdev(desc->intf),
-                          desc->bMaxPacketSize0,
-                          desc->inbuf,
-                          desc->response->transfer_dma);
+        spin_lock(&wdm_device_list_lock);
+        list_del(&desc->device_list);
+        spin_unlock(&wdm_device_list_lock);
+        kfree(desc->sbuf);
+        kfree(desc->inbuf);
         kfree(desc->orq);
         kfree(desc->irq);
         kfree(desc->ubuf);
@@ -323,7 +352,7 @@ static ssize_t wdm_write
         }
 
         /* concurrent writes and disconnect */
-        r = mutex_lock_interruptible(&desc->lock);
+        r = mutex_lock_interruptible(&desc->wlock);
         rv = -ERESTARTSYS;
         if (r) {
                 kfree(buf);
@@ -348,6 +377,10 @@ static ssize_t wdm_write
         else
                 if (test_bit(WDM_IN_USE, &desc->flags))
                         r = -EAGAIN;
+
+        if (test_bit(WDM_RESETTING, &desc->flags))
+                r = -EIO;
+
         if (r < 0) {
                 kfree(buf);
                 goto out;
@@ -386,7 +419,7 @@ static ssize_t wdm_write
 out:
         usb_autopm_put_interface(desc->intf);
 outnp:
-        mutex_unlock(&desc->lock);
+        mutex_unlock(&desc->wlock);
 outnl:
         return rv < 0 ? rv : count;
 }
@@ -394,16 +427,17 @@ outnl:
 static ssize_t wdm_read
 (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
 {
-        int rv, cntr = 0;
+        int rv, cntr;
         int i = 0;
         struct wdm_device *desc = file->private_data;
 
 
-        rv = mutex_lock_interruptible(&desc->lock); /*concurrent reads */
+        rv = mutex_lock_interruptible(&desc->rlock); /*concurrent reads */
         if (rv < 0)
                 return -ERESTARTSYS;
 
-        if (desc->length == 0) {
+        cntr = ACCESS_ONCE(desc->length);
+        if (cntr == 0) {
                 desc->read = 0;
 retry:
                 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
@@ -427,6 +461,10 @@ retry:
                         rv = -ENODEV;
                         goto err;
                 }
+                if (test_bit(WDM_RESETTING, &desc->flags)) {
+                        rv = -EIO;
+                        goto err;
+                }
                 usb_mark_last_busy(interface_to_usbdev(desc->intf));
                 if (rv < 0) {
                         rv = -ERESTARTSYS;
@@ -453,17 +491,20 @@ retry:
                         spin_unlock_irq(&desc->iuspin);
                         goto retry;
                 }
-                clear_bit(WDM_READ, &desc->flags);
+                cntr = desc->length;
                 spin_unlock_irq(&desc->iuspin);
         }
 
-        cntr = count > desc->length ? desc->length : count;
+        if (cntr > count)
+                cntr = count;
         rv = copy_to_user(buffer, desc->ubuf, cntr);
         if (rv > 0) {
                 rv = -EFAULT;
                 goto err;
         }
 
+        spin_lock_irq(&desc->iuspin);
+
         for (i = 0; i < desc->length - cntr; i++)
                 desc->ubuf[i] = desc->ubuf[i + cntr];
 
@@ -471,10 +512,13 @@ retry:
         /* in case we had outstanding data */
         if (!desc->length)
                 clear_bit(WDM_READ, &desc->flags);
+
+        spin_unlock_irq(&desc->iuspin);
+
         rv = cntr;
 
 err:
-        mutex_unlock(&desc->lock);
+        mutex_unlock(&desc->rlock);
         return rv;
 }
 
@@ -524,11 +568,11 @@ static int wdm_open(struct inode *inode, struct file *file)
         struct wdm_device *desc;
 
         mutex_lock(&wdm_mutex);
-        intf = usb_find_interface(&wdm_driver, minor);
-        if (!intf)
+        desc = wdm_find_device_by_minor(minor);
+        if (!desc)
                 goto out;
 
-        desc = usb_get_intfdata(intf);
+        intf = desc->intf;
         if (test_bit(WDM_DISCONNECTING, &desc->flags))
                 goto out;
         file->private_data = desc;
@@ -538,9 +582,9 @@ static int wdm_open(struct inode *inode, struct file *file)
                 dev_err(&desc->intf->dev, "Error autopm - %d\n", rv);
                 goto out;
         }
-        intf->needs_remote_wakeup = 1;
 
-        mutex_lock(&desc->lock);
+        /* using write lock to protect desc->count */
+        mutex_lock(&desc->wlock);
         if (!desc->count++) {
                 desc->werr = 0;
                 desc->rerr = 0;
@@ -553,7 +597,9 @@ static int wdm_open(struct inode *inode, struct file *file)
         } else {
                 rv = 0;
         }
-        mutex_unlock(&desc->lock);
+        mutex_unlock(&desc->wlock);
+        if (desc->count == 1)
+                desc->manage_power(intf, 1);
         usb_autopm_put_interface(desc->intf);
 out:
         mutex_unlock(&wdm_mutex);
@@ -565,15 +611,17 @@ static int wdm_release(struct inode *inode, struct file *file)
         struct wdm_device *desc = file->private_data;
 
         mutex_lock(&wdm_mutex);
-        mutex_lock(&desc->lock);
+
+        /* using write lock to protect desc->count */
+        mutex_lock(&desc->wlock);
         desc->count--;
-        mutex_unlock(&desc->lock);
+        mutex_unlock(&desc->wlock);
 
         if (!desc->count) {
                 dev_dbg(&desc->intf->dev, "wdm_release: cleanup");
                 kill_urbs(desc);
                 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
-                        desc->intf->needs_remote_wakeup = 0;
+                        desc->manage_power(desc->intf, 0);
         }
         mutex_unlock(&wdm_mutex);
         return 0;
@@ -620,70 +668,31 @@ static void wdm_rxwork(struct work_struct *work)
 
 /* --- hotplug --- */
 
-static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id)
+static int wdm_create(struct usb_interface *intf, struct usb_endpoint_descriptor *ep,
+                u16 bufsize, int (*manage_power)(struct usb_interface *, int))
 {
-        int rv = -EINVAL;
-        struct usb_device *udev = interface_to_usbdev(intf);
+        int rv = -ENOMEM;
         struct wdm_device *desc;
-        struct usb_host_interface *iface;
-        struct usb_endpoint_descriptor *ep;
-        struct usb_cdc_dmm_desc *dmhd;
-        u8 *buffer = intf->altsetting->extra;
-        int buflen = intf->altsetting->extralen;
-        u16 maxcom = 0;
-
-        if (!buffer)
-                goto out;
-
-        while (buflen > 2) {
-                if (buffer [1] != USB_DT_CS_INTERFACE) {
-                        dev_err(&intf->dev, "skipping garbage\n");
-                        goto next_desc;
-                }
-
-                switch (buffer [2]) {
-                case USB_CDC_HEADER_TYPE:
-                        break;
-                case USB_CDC_DMM_TYPE:
-                        dmhd = (struct usb_cdc_dmm_desc *)buffer;
-                        maxcom = le16_to_cpu(dmhd->wMaxCommand);
-                        dev_dbg(&intf->dev,
-                                "Finding maximum buffer length: %d", maxcom);
-                        break;
-                default:
-                        dev_err(&intf->dev,
-                                "Ignoring extra header, type %d, length %d\n",
-                                buffer[2], buffer[0]);
-                        break;
-                }
-next_desc:
-                buflen -= buffer[0];
-                buffer += buffer[0];
-        }
 
-        rv = -ENOMEM;
         desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL);
         if (!desc)
                 goto out;
-        mutex_init(&desc->lock);
+        INIT_LIST_HEAD(&desc->device_list);
+        mutex_init(&desc->rlock);
+        mutex_init(&desc->wlock);
         spin_lock_init(&desc->iuspin);
         init_waitqueue_head(&desc->wait);
-        desc->wMaxCommand = maxcom;
+        desc->wMaxCommand = bufsize;
         /* this will be expanded and needed in hardware endianness */
         desc->inum = cpu_to_le16((u16)intf->cur_altsetting->desc.bInterfaceNumber);
         desc->intf = intf;
         INIT_WORK(&desc->rxwork, wdm_rxwork);
 
         rv = -EINVAL;
-        iface = intf->cur_altsetting;
-        if (iface->desc.bNumEndpoints != 1)
-                goto err;
-        ep = &iface->endpoint[0].desc;
-        if (!ep || !usb_endpoint_is_int_in(ep))
+        if (!usb_endpoint_is_int_in(ep))
                 goto err;
 
         desc->wMaxPacketSize = usb_endpoint_maxp(ep);
-        desc->bMaxPacketSize0 = udev->descriptor.bMaxPacketSize0;
 
         desc->orq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
         if (!desc->orq)
@@ -708,19 +717,13 @@ next_desc:
         if (!desc->ubuf)
                 goto err;
 
-        desc->sbuf = usb_alloc_coherent(interface_to_usbdev(intf),
-                                        desc->wMaxPacketSize,
-                                        GFP_KERNEL,
-                                        &desc->validity->transfer_dma);
+        desc->sbuf = kmalloc(desc->wMaxPacketSize, GFP_KERNEL);
         if (!desc->sbuf)
                 goto err;
 
-        desc->inbuf = usb_alloc_coherent(interface_to_usbdev(intf),
-                                         desc->bMaxPacketSize0,
-                                         GFP_KERNEL,
-                                         &desc->response->transfer_dma);
+        desc->inbuf = kmalloc(desc->wMaxCommand, GFP_KERNEL);
         if (!desc->inbuf)
-                goto err2;
+                goto err;
 
         usb_fill_int_urb(
                 desc->validity,
@@ -732,45 +735,149 @@ next_desc:
                 desc,
                 ep->bInterval
         );
-        desc->validity->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 
-        usb_set_intfdata(intf, desc);
+        desc->irq->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE);
+        desc->irq->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE;
+        desc->irq->wValue = 0;
+        desc->irq->wIndex = desc->inum;
+        desc->irq->wLength = cpu_to_le16(desc->wMaxCommand);
+
+        usb_fill_control_urb(
+                desc->response,
+                interface_to_usbdev(intf),
+                /* using common endpoint 0 */
+                usb_rcvctrlpipe(interface_to_usbdev(desc->intf), 0),
+                (unsigned char *)desc->irq,
+                desc->inbuf,
+                desc->wMaxCommand,
+                wdm_in_callback,
+                desc
+        );
+
+        desc->manage_power = manage_power;
+
+        spin_lock(&wdm_device_list_lock);
+        list_add(&desc->device_list, &wdm_device_list);
+        spin_unlock(&wdm_device_list_lock);
+
         rv = usb_register_dev(intf, &wdm_class);
         if (rv < 0)
-                goto err3;
+                goto err;
         else
-                dev_info(&intf->dev, "cdc-wdm%d: USB WDM device\n",
-                        intf->minor - WDM_MINOR_BASE);
+                dev_info(&intf->dev, "%s: USB WDM device\n", dev_name(intf->usb_dev));
 out:
         return rv;
-err3:
-        usb_set_intfdata(intf, NULL);
-        usb_free_coherent(interface_to_usbdev(desc->intf),
-                          desc->bMaxPacketSize0,
-                        desc->inbuf,
-                        desc->response->transfer_dma);
-err2:
-        usb_free_coherent(interface_to_usbdev(desc->intf),
-                          desc->wMaxPacketSize,
-                          desc->sbuf,
-                          desc->validity->transfer_dma);
 err:
-        free_urbs(desc);
-        kfree(desc->ubuf);
-        kfree(desc->orq);
-        kfree(desc->irq);
-        kfree(desc);
+        cleanup(desc);
+        return rv;
+}
+
+static int wdm_manage_power(struct usb_interface *intf, int on)
+{
+        /* need autopm_get/put here to ensure the usbcore sees the new value */
+        int rv = usb_autopm_get_interface(intf);
+        if (rv < 0)
+                goto err;
+
+        intf->needs_remote_wakeup = on;
+        usb_autopm_put_interface(intf);
+err:
         return rv;
 }
 
+static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id)
+{
+        int rv = -EINVAL;
+        struct usb_host_interface *iface;
+        struct usb_endpoint_descriptor *ep;
+        struct usb_cdc_dmm_desc *dmhd;
+        u8 *buffer = intf->altsetting->extra;
+        int buflen = intf->altsetting->extralen;
+        u16 maxcom = WDM_DEFAULT_BUFSIZE;
+
+        if (!buffer)
+                goto err;
+        while (buflen > 2) {
+                if (buffer[1] != USB_DT_CS_INTERFACE) {
+                        dev_err(&intf->dev, "skipping garbage\n");
+                        goto next_desc;
+                }
+
+                switch (buffer[2]) {
+                case USB_CDC_HEADER_TYPE:
+                        break;
+                case USB_CDC_DMM_TYPE:
+                        dmhd = (struct usb_cdc_dmm_desc *)buffer;
+                        maxcom = le16_to_cpu(dmhd->wMaxCommand);
+                        dev_dbg(&intf->dev,
+                                "Finding maximum buffer length: %d", maxcom);
+                        break;
+                default:
+                        dev_err(&intf->dev,
+                                "Ignoring extra header, type %d, length %d\n",
+                                buffer[2], buffer[0]);
+                        break;
+                }
+next_desc:
+                buflen -= buffer[0];
+                buffer += buffer[0];
+        }
+
+        iface = intf->cur_altsetting;
+        if (iface->desc.bNumEndpoints != 1)
+                goto err;
+        ep = &iface->endpoint[0].desc;
+
+        rv = wdm_create(intf, ep, maxcom, &wdm_manage_power);
+
+err:
+        return rv;
+}
+
+/**
+ * usb_cdc_wdm_register - register a WDM subdriver
+ * @intf: usb interface the subdriver will associate with
+ * @ep: interrupt endpoint to monitor for notifications
+ * @bufsize: maximum message size to support for read/write
+ *
+ * Create WDM usb class character device and associate it with intf
+ * without binding, allowing another driver to manage the interface.
+ *
+ * The subdriver will manage the given interrupt endpoint exclusively
+ * and will issue control requests referring to the given intf. It
+ * will otherwise avoid interferring, and in particular not do
+ * usb_set_intfdata/usb_get_intfdata on intf.
+ *
+ * The return value is a pointer to the subdriver's struct usb_driver.
+ * The registering driver is responsible for calling this subdriver's
+ * disconnect, suspend, resume, pre_reset and post_reset methods from
+ * its own.
+ */
+struct usb_driver *usb_cdc_wdm_register(struct usb_interface *intf,
+                                        struct usb_endpoint_descriptor *ep,
+                                        int bufsize,
+                                        int (*manage_power)(struct usb_interface *, int))
+{
+        int rv = -EINVAL;
+
+        rv = wdm_create(intf, ep, bufsize, manage_power);
+        if (rv < 0)
+                goto err;
+
+        return &wdm_driver;
+err:
+        return ERR_PTR(rv);
+}
+EXPORT_SYMBOL(usb_cdc_wdm_register);
+
 static void wdm_disconnect(struct usb_interface *intf)
 {
         struct wdm_device *desc;
         unsigned long flags;
 
         usb_deregister_dev(intf, &wdm_class);
+        desc = wdm_find_device(intf);
         mutex_lock(&wdm_mutex);
-        desc = usb_get_intfdata(intf);
 
         /* the spinlock makes sure no new urbs are generated in the callbacks */
         spin_lock_irqsave(&desc->iuspin, flags);
@@ -779,11 +886,13 @@ static void wdm_disconnect(struct usb_interface *intf)
         /* to terminate pending flushes */
         clear_bit(WDM_IN_USE, &desc->flags);
         spin_unlock_irqrestore(&desc->iuspin, flags);
-        mutex_lock(&desc->lock);
+        wake_up_all(&desc->wait);
+        mutex_lock(&desc->rlock);
+        mutex_lock(&desc->wlock);
         kill_urbs(desc);
         cancel_work_sync(&desc->rxwork);
-        mutex_unlock(&desc->lock);
-        wake_up_all(&desc->wait);
+        mutex_unlock(&desc->wlock);
+        mutex_unlock(&desc->rlock);
         if (!desc->count)
                 cleanup(desc);
         mutex_unlock(&wdm_mutex);
@@ -792,14 +901,16 @@ static void wdm_disconnect(struct usb_interface *intf)
 #ifdef CONFIG_PM
 static int wdm_suspend(struct usb_interface *intf, pm_message_t message)
 {
-        struct wdm_device *desc = usb_get_intfdata(intf);
+        struct wdm_device *desc = wdm_find_device(intf);
         int rv = 0;
 
         dev_dbg(&desc->intf->dev, "wdm%d_suspend\n", intf->minor);
 
         /* if this is an autosuspend the caller does the locking */
-        if (!PMSG_IS_AUTO(message))
-                mutex_lock(&desc->lock);
+        if (!PMSG_IS_AUTO(message)) {
+                mutex_lock(&desc->rlock);
+                mutex_lock(&desc->wlock);
+        }
         spin_lock_irq(&desc->iuspin);
 
         if (PMSG_IS_AUTO(message) &&
@@ -815,8 +926,10 @@ static int wdm_suspend(struct usb_interface *intf, pm_message_t message)
                 kill_urbs(desc);
                 cancel_work_sync(&desc->rxwork);
         }
-        if (!PMSG_IS_AUTO(message))
-                mutex_unlock(&desc->lock);
+        if (!PMSG_IS_AUTO(message)) {
+                mutex_unlock(&desc->wlock);
+                mutex_unlock(&desc->rlock);
+        }
 
         return rv;
 }
@@ -838,7 +951,7 @@ static int recover_from_urb_loss(struct wdm_device *desc)
 #ifdef CONFIG_PM
 static int wdm_resume(struct usb_interface *intf)
 {
-        struct wdm_device *desc = usb_get_intfdata(intf);
+        struct wdm_device *desc = wdm_find_device(intf);
         int rv;
 
         dev_dbg(&desc->intf->dev, "wdm%d_resume\n", intf->minor);
@@ -852,10 +965,7 @@ static int wdm_resume(struct usb_interface *intf)
 
 static int wdm_pre_reset(struct usb_interface *intf)
 {
-        struct wdm_device *desc = usb_get_intfdata(intf);
-
-        mutex_lock(&desc->lock);
-        kill_urbs(desc);
+        struct wdm_device *desc = wdm_find_device(intf);
 
         /*
          * we notify everybody using poll of
@@ -864,19 +974,28 @@ static int wdm_pre_reset(struct usb_interface *intf)
          * message from the device is lost
          */
         spin_lock_irq(&desc->iuspin);
+        set_bit(WDM_RESETTING, &desc->flags);   /* inform read/write */
+        set_bit(WDM_READ, &desc->flags);        /* unblock read */
+        clear_bit(WDM_IN_USE, &desc->flags);    /* unblock write */
         desc->rerr = -EINTR;
         spin_unlock_irq(&desc->iuspin);
         wake_up_all(&desc->wait);
+        mutex_lock(&desc->rlock);
+        mutex_lock(&desc->wlock);
+        kill_urbs(desc);
+        cancel_work_sync(&desc->rxwork);
         return 0;
 }
 
 static int wdm_post_reset(struct usb_interface *intf)
 {
-        struct wdm_device *desc = usb_get_intfdata(intf);
+        struct wdm_device *desc = wdm_find_device(intf);
         int rv;
 
+        clear_bit(WDM_RESETTING, &desc->flags);
         rv = recover_from_urb_loss(desc);
-        mutex_unlock(&desc->lock);
+        mutex_unlock(&desc->wlock);
+        mutex_unlock(&desc->rlock);
         return 0;
 }