{
        if (info->read_subdevice)
                return info->read_subdevice;
-       if (info->device == NULL)
-               return NULL;
-       return info->device->read_subdev;
+       if (info->device)
+               return info->device->read_subdev;
+       return NULL;
 }
 
 static struct comedi_subdevice *
 {
        if (info->write_subdevice)
                return info->write_subdevice;
-       if (info->device == NULL)
-               return NULL;
-       return info->device->write_subdev;
+       if (info->device)
+               return info->device->write_subdev;
+       return NULL;
 }
 
 static int resize_async_buffer(struct comedi_device *dev,