staging: comedi: quatech_daqp_cs: use comedi_offset_munge() in ao (*insn_write)

Use the comedi_offset_munge() helper to do the offset binary to two's
complement conversion when writing a new analog output value.

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/quatech_daqp_cs.c b/drivers/staging/comedi/drivers/quatech_daqp_cs.c
index cf144ce..4f87147 100644 (file)
--- a/drivers/staging/comedi/drivers/quatech_daqp_cs.c
+++ b/drivers/staging/comedi/drivers/quatech_daqp_cs.c
@@ -655,11 +655,9 @@ static int daqp_ao_insn_write(struct comedi_device *dev,
 
                s->readback[chan] = val;
 
-               val &= 0x0fff;
-               val ^= 0x0800;          /* Flip the sign */
-               val |= (chan << 12);
-
-               outw(val, dev->iobase + DAQP_DA);
+               /* write the two's complement value to the channel */
+               outw((chan << 12) | comedi_offset_munge(s, val),
+                    dev->iobase + DAQP_DA);
        }
 
        return insn->n;