staging: comedi: das16: use COMEDI_CB_CANCEL_MASK to see if command is running

In das16_interrupt(), use COMEDI_CB_CANCEL_MASK to determine if the async
command is still running and the dma needs to be re-enabled. This will
cause the driver not re-enable the dma if the async buffer overflows
(COMEDI_CB_OVERFLOW), a hardware error occurs (COMEDI_CB_ERROR), or the
command completes (COMEDI_CB_EOA).

Signed-off-by: H Hartley Sweeten <[email protected]>
Reviewed-by: Ian Abbott <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: bigguiness

drivers/staging/comedi/drivers/das16.c

@@ -523,7 +523,7 @@ static void das16_interrupt(struct comedi_device *dev)
 	devpriv->adc_byte_count -= num_bytes;
 
 	/* re-enable dma */
-	if ((async->events & COMEDI_CB_EOA) == 0) {
+	if (!(async->events & COMEDI_CB_CANCEL_MASK)) {
 		struct comedi_isadma_desc *nxt_desc = &dma->desc[dma->cur_dma];
 
 		nxt_desc->size = nxt_desc->maxsize;