struct usbduxfast_private *devpriv = dev->private;
        int ret;
 
-       if (!devpriv)
-               return -EFAULT;
-
        down(&devpriv->sem);
        ret = usbduxfast_ai_stop(dev, 1);
        up(&devpriv->sem);
        struct usbduxfast_private *devpriv = dev->private;
        int ret;
 
-       if (!devpriv)
-               return -EFAULT;
-
        usb_fill_bulk_urb(devpriv->urb, usb, usb_rcvbulkpipe(usb, BULKINEP),
                          devpriv->inbuf, SIZEINBUF,
                          usbduxfast_ai_interrupt, dev);
        struct comedi_cmd *cmd = &s->async->cmd;
        int ret;
 
-       if (!devpriv)
-               return -EFAULT;
-
        if (trig_num != cmd->start_arg)
                return -EINVAL;
 
        int result;
        long steps, steps_tmp;
 
-       if (!devpriv)
-               return -EFAULT;
-
        down(&devpriv->sem);
        if (devpriv->ai_cmd_running) {
                dev_err(dev->class_dev, "ai_cmd not possible\n");