return 0;
 }
 
-static void pci9118_exttrg_add(struct comedi_device *dev)
+static void pci9118_exttrg_enable(struct comedi_device *dev, bool enable)
 {
        struct pci9118_private *devpriv = dev->private;
 
-       devpriv->int_ctrl |= PCI9118_INT_CTRL_DTRG;
+       if (enable)
+               devpriv->int_ctrl |= PCI9118_INT_CTRL_DTRG;
+       else
+               devpriv->int_ctrl &= ~PCI9118_INT_CTRL_DTRG;
        outl(devpriv->int_ctrl, dev->iobase + PCI9118_INT_CTRL_REG);
-       pci9118_amcc_int_ena(dev, true);
-}
-
-static void pci9118_exttrg_del(struct comedi_device *dev)
-{
-       struct pci9118_private *devpriv = dev->private;
 
-       devpriv->int_ctrl &= ~PCI9118_INT_CTRL_DTRG;
-       if (!devpriv->int_ctrl)
+       if (devpriv->int_ctrl)
+               pci9118_amcc_int_ena(dev, true);
+       else
                pci9118_amcc_int_ena(dev, false);
-       outl(devpriv->int_ctrl, dev->iobase + PCI9118_INT_CTRL_REG);
 }
 
 static void pci9118_calc_divisors(char mode, struct comedi_device *dev,
 
        if (devpriv->usedma)
                pci9118_amcc_dma_ena(dev, false);
-       pci9118_exttrg_del(dev);
+       pci9118_exttrg_enable(dev, false);
        pci9118_start_pacer(dev, 0);    /* stop 8254 counters */
        /* set default config (disable burst and triggers) */
        devpriv->ai_cfg = PCI9118_AI_CFG_PDTRG | PCI9118_AI_CFG_PETRG;
                                /* deactivate EXT trigger */
                                devpriv->ai12_startstop &= ~START_AI_EXT;
                                if (!(devpriv->ai12_startstop & STOP_AI_EXT))
-                                       pci9118_exttrg_del(dev);
+                                       pci9118_exttrg_enable(dev, false);
 
                                /* start pacer */
                                pci9118_start_pacer(dev, devpriv->ai_do);
                        } else if (devpriv->ai12_startstop & STOP_AI_EXT) {
                                /* deactivate EXT trigger */
                                devpriv->ai12_startstop &= ~STOP_AI_EXT;
-                               pci9118_exttrg_del(dev);
+                               pci9118_exttrg_enable(dev, false);
 
                                /* on next interrupt measure will stop */
                                devpriv->ai_neverending = 0;
        }
 
        if (devpriv->ai12_startstop)
-               pci9118_exttrg_add(dev);
-                                               /* activate EXT trigger */
+               pci9118_exttrg_enable(dev, true);
 
        if ((devpriv->ai_do == 1) || (devpriv->ai_do == 2))
                devpriv->int_ctrl |= PCI9118_INT_CTRL_TIMER;
                return -EIO;
        }
 
-       if (devpriv->ai12_startstop) {
-               pci9118_exttrg_add(dev);
-                                               /* activate EXT trigger */
-       }
+       if (devpriv->ai12_startstop)
+               pci9118_exttrg_enable(dev, true);
 
        outl(0x02000000 | AINT_WRITE_COMPL,
             devpriv->iobase_a + AMCC_OP_REG_INTCSR);