4 files changed, 34 insertions, 3 deletions

diff --git a/drivers/media/video/uvc/uvc_driver.c b/drivers/media/video/uvc/uvc_driver.c
index f4fced34cfd7..3287454bb368 100644
--- a/drivers/media/video/uvc/uvc_driver.c
+++ b/drivers/media/video/uvc/uvc_driver.c
@@ -1594,6 +1594,7 @@ static int uvc_probe(struct usb_interface *intf,
         INIT_LIST_HEAD(&dev->entities);
         INIT_LIST_HEAD(&dev->streaming);
         kref_init(&dev->kref);
+        atomic_set(&dev->users, 0);
 
         dev->udev = usb_get_dev(udev);
         dev->intf = usb_get_intf(intf);
diff --git a/drivers/media/video/uvc/uvc_status.c b/drivers/media/video/uvc/uvc_status.c
index 21d87124986b..f152a9903862 100644
--- a/drivers/media/video/uvc/uvc_status.c
+++ b/drivers/media/video/uvc/uvc_status.c
@@ -194,7 +194,7 @@ int uvc_status_init(struct uvc_device *dev)
                 dev->status, UVC_MAX_STATUS_SIZE, uvc_status_complete,
                 dev, interval);
 
-        return usb_submit_urb(dev->int_urb, GFP_KERNEL);
+        return 0;
 }
 
 void uvc_status_cleanup(struct uvc_device *dev)
@@ -205,15 +205,30 @@ void uvc_status_cleanup(struct uvc_device *dev)
         uvc_input_cleanup(dev);
 }
 
-int uvc_status_suspend(struct uvc_device *dev)
+int uvc_status_start(struct uvc_device *dev)
+{
+        if (dev->int_urb == NULL)
+                return 0;
+
+        return usb_submit_urb(dev->int_urb, GFP_KERNEL);
+}
+
+void uvc_status_stop(struct uvc_device *dev)
 {
         usb_kill_urb(dev->int_urb);
+}
+
+int uvc_status_suspend(struct uvc_device *dev)
+{
+        if (atomic_read(&dev->users))
+                usb_kill_urb(dev->int_urb);
+
         return 0;
 }
 
 int uvc_status_resume(struct uvc_device *dev)
 {
-        if (dev->int_urb == NULL)
+        if (dev->int_urb == NULL || atomic_read(&dev->users) == 0)
                 return 0;
 
         return usb_submit_urb(dev->int_urb, GFP_NOIO);
diff --git a/drivers/media/video/uvc/uvc_v4l2.c b/drivers/media/video/uvc/uvc_v4l2.c
index ad7e64ff3add..507542dcbdae 100644
--- a/drivers/media/video/uvc/uvc_v4l2.c
+++ b/drivers/media/video/uvc/uvc_v4l2.c
@@ -439,6 +439,15 @@ static int uvc_v4l2_open(struct file *file)
                 goto done;
         }
 
+        if (atomic_inc_return(&video->dev->users) == 1) {
+                if ((ret = uvc_status_start(video->dev)) < 0) {
+                        usb_autopm_put_interface(video->dev->intf);
+                        atomic_dec(&video->dev->users);
+                        kfree(handle);
+                        goto done;
+                }
+        }
+
         handle->device = video;
         handle->state = UVC_HANDLE_PASSIVE;
         file->private_data = handle;
@@ -473,6 +482,9 @@ static int uvc_v4l2_release(struct file *file)
         kfree(handle);
         file->private_data = NULL;
 
+        if (atomic_dec_return(&video->dev->users) == 0)
+                uvc_status_stop(video->dev);
+
         usb_autopm_put_interface(video->dev->intf);
         kref_put(&video->dev->kref, uvc_delete);
         return 0;
diff --git a/drivers/media/video/uvc/uvcvideo.h b/drivers/media/video/uvc/uvcvideo.h
index e5014e668f99..daf074447304 100644
--- a/drivers/media/video/uvc/uvcvideo.h
+++ b/drivers/media/video/uvc/uvcvideo.h
@@ -634,6 +634,7 @@ struct uvc_device {
         enum uvc_device_state state;
         struct kref kref;
         struct list_head list;
+        atomic_t users;
 
         /* Video control interface */
         __u16 uvc_version;
@@ -770,6 +771,8 @@ extern int uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit,
 /* Status */
 extern int uvc_status_init(struct uvc_device *dev);
 extern void uvc_status_cleanup(struct uvc_device *dev);
+extern int uvc_status_start(struct uvc_device *dev);
+extern void uvc_status_stop(struct uvc_device *dev);
 extern int uvc_status_suspend(struct uvc_device *dev);
 extern int uvc_status_resume(struct uvc_device *dev);