staging: comedi: addi_apci_2032: set COMEDI_CB_OVERFLOW

If the call to `comedi_buf_put()` fails in the interrupt routine, set
the `COMEDI_CB_OVERFLOW` event flag.  Note that the `COMEDI_CB_ERROR`
flag will have also been set by `comedi_buf_put()` in this case.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/addi_apci_2032.c

@@ -248,8 +248,10 @@ static irqreturn_t apci2032_interrupt(int irq, void *d)
 	s->state = inl(dev->iobase + APCI2032_INT_STATUS_REG);
 	outl(0x0, dev->iobase + APCI2032_INT_CTRL_REG);
 
-	comedi_buf_put(s->async, s->state);
-	s->async->events |= COMEDI_CB_BLOCK | COMEDI_CB_EOS;
+	if (comedi_buf_put(s->async, s->state))
+		s->async->events |= COMEDI_CB_BLOCK | COMEDI_CB_EOS;
+	else
+		s->async->events |= COMEDI_CB_OVERFLOW;
 	comedi_event(dev, s);
 
 	return IRQ_HANDLED;