[media] em28xx: refactor the code in em28xx_usb_disconnect()

The main purpose of this patch is to move the call of em28xx_release_resources()
after the call of em28xx_close_extension().
This is necessary, because some resources might be needed/used by the extensions
fini() functions when they get closed.
Also mark the device as disconnected earlier in this function and unify the
em28xx_uninit_usb_xfer() calls for analog and digital mode.
Signed-off-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/usb/em28xx/em28xx-cards.c

@@ -3507,6 +3507,8 @@ static void em28xx_usb_disconnect(struct usb_interface *interface)
 	if (!dev)
 		return;
 
+	dev->disconnected = 1;
+
 	if (dev->is_audio_only) {
 		mutex_lock(&dev->lock);
 		em28xx_close_extension(dev);
@@ -3518,31 +3520,25 @@ static void em28xx_usb_disconnect(struct usb_interface *interface)
 
 	flush_request_modules(dev);
 
-	/* wait until all current v4l2 io is finished then deallocate
-	   resources */
 	mutex_lock(&dev->lock);
 
 	v4l2_device_disconnect(&dev->v4l2_dev);
 
 	if (dev->users) {
-		em28xx_warn
-		    ("device %s is open! Deregistration and memory "
-		     "deallocation are deferred on close.\n",
+		em28xx_warn("device %s is open! Deregistration and memory deallocation are deferred on close.\n",
 			    video_device_node_name(dev->vdev));
 
-		em28xx_uninit_usb_xfer(dev, dev->mode);
-		dev->disconnected = 1;
-	} else {
-		dev->disconnected = 1;
-		em28xx_release_resources(dev);
+		em28xx_uninit_usb_xfer(dev, EM28XX_ANALOG_MODE);
+		em28xx_uninit_usb_xfer(dev, EM28XX_DIGITAL_MODE);
 	}
 
-	/* free DVB isoc buffers */
-	em28xx_uninit_usb_xfer(dev, EM28XX_DIGITAL_MODE);
+	em28xx_close_extension(dev);
+	/* NOTE: must be called BEFORE the resources are released */
 
-	mutex_unlock(&dev->lock);
+	if (!dev->users)
+		em28xx_release_resources(dev);
 
-	em28xx_close_extension(dev);
+	mutex_unlock(&dev->lock);
 
 	if (!dev->users) {
 		kfree(dev->alt_max_pkt_size_isoc);