staging: comedi: adl_pci6208: use comedi_offset_munge()

Use comedi_offset_munge() to munge the offset binary values from the
comedi core into the two's complement form that the hardware expects.

This removes the hard coded assumption that the analog outputs are
16-bits and instead does the munging based on the s->maxdata.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/adl_pci6208.c b/drivers/staging/comedi/drivers/adl_pci6208.c
index 059d7ea..db80873 100644 (file)
--- a/drivers/staging/comedi/drivers/adl_pci6208.c
+++ b/drivers/staging/comedi/drivers/adl_pci6208.c
@@ -104,7 +104,6 @@ static int pci6208_ao_winsn(struct comedi_device *dev,
 {
        struct pci6208_private *devpriv = dev->private;
        int chan = CR_CHAN(insn->chanspec);
-       unsigned int invert = 1 << (16 - 1);
        unsigned int val = devpriv->ao_readback[chan];
        int ret;
        int i;
@@ -117,7 +116,9 @@ static int pci6208_ao_winsn(struct comedi_device *dev,
                if (ret)
                        return ret;
 
-               outw(val ^ invert, dev->iobase + PCI6208_AO_CONTROL(chan));
+               /* the hardware expects two's complement values */
+               outw(comedi_offset_munge(s, val),
+                    dev->iobase + PCI6208_AO_CONTROL(chan));
        }
        devpriv->ao_readback[chan] = val;