tweaked previous fix to be extra safe

diff --git a/comedi/drivers/das800.c b/comedi/drivers/das800.c
index b0f5c40976c6c481d0b83e5cf11b8a245e6ed229..21f50fbb8db0d7585a9cf2bfbd3775a3b8030d4b 100644 (file)
--- a/comedi/drivers/das800.c
+++ b/comedi/drivers/das800.c
@@ -332,9 +332,12 @@ static void das800_interrupt(int irq, void *d, struct pt_regs *regs)
        comedi_spin_lock_irqsave(&devpriv->spinlock, irq_flags);
        outb(CONTROL1, dev->iobase + DAS800_GAIN);      /* select base address + 7 to be STATUS2 register */
        status = inb(dev->iobase + DAS800_STATUS2) & STATUS2_HCEN;
-       comedi_spin_unlock_irqrestore(&devpriv->spinlock, irq_flags);
+       /* don't release spinlock yet since we want to make sure noone else disables hardware conversions */
        if(status == 0)
+       {
+               comedi_spin_unlock_irqrestore(&devpriv->spinlock, irq_flags);
                return;
+       }
 
   /* read 16 bits from dev->iobase and dev->iobase + 1 */
        dataPoint = inb(dev->iobase + DAS800_LSB);
@@ -374,6 +377,8 @@ static void das800_interrupt(int irq, void *d, struct pt_regs *regs)
                dataPoint = inb(dev->iobase + DAS800_LSB);
                dataPoint += inb(dev->iobase + DAS800_MSB) << 8;
        }
+       /* we can release spinlock now since we dont case if hardware conversions are enabled anymore */
+       comedi_spin_unlock_irqrestore(&devpriv->spinlock, irq_flags);
        if(i == max_loops)
                comedi_error(dev, "possible problem with loop in interrupt handler");