staging: comedi: ni_at_ao: introduce atao_select_reg_group()

To clarify the code a bit, introduce a helper function to set/clear
the GRP2WR bit in the CFG1 register. This bit selects which group of
registers are used for the registers that share the same I/O addresses.

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/ni_at_ao.c b/drivers/staging/comedi/drivers/ni_at_ao.c
index 7803ad184214f4c0c41e4abfd3d2dc7d01676ad0..65c4712966a0c35f5de3eb8900a93c30266eea77 100644 (file)
--- a/drivers/staging/comedi/drivers/ni_at_ao.c
+++ b/drivers/staging/comedi/drivers/ni_at_ao.c
@@ -124,6 +124,17 @@ struct atao_private {
        unsigned char caldac[21];
 };
 
+static void atao_select_reg_group(struct comedi_device *dev, int group)
+{
+       struct atao_private *devpriv = dev->private;
+
+       if (group)
+               devpriv->cfg1 |= ATAO_CFG1_GRP2WR;
+       else
+               devpriv->cfg1 &= ~ATAO_CFG1_GRP2WR;
+       outw(devpriv->cfg1, dev->iobase + ATAO_CFG1_REG);
+}
+
 static int atao_ao_winsn(struct comedi_device *dev, struct comedi_subdevice *s,
                         struct comedi_insn *insn, unsigned int *data)
 {
@@ -134,15 +145,11 @@ static int atao_ao_winsn(struct comedi_device *dev, struct comedi_subdevice *s,
 
        for (i = 0; i < insn->n; i++) {
                bits = data[i] - 0x800;
-               if (chan == 0) {
-                       devpriv->cfg1 |= ATAO_CFG1_GRP2WR;
-                       outw(devpriv->cfg1, dev->iobase + ATAO_CFG1_REG);
-               }
+               if (chan == 0)
+                       atao_select_reg_group(dev, 1);
                outw(bits, dev->iobase + ATAO_AO_REG(chan));
-               if (chan == 0) {
-                       devpriv->cfg1 &= ~ATAO_CFG1_GRP2WR;
-                       outw(devpriv->cfg1, dev->iobase + ATAO_CFG1_REG);
-               }
+               if (chan == 0)
+                       atao_select_reg_group(dev, 0);
                devpriv->ao_readback[chan] = data[i];
        }
 
@@ -312,15 +319,11 @@ static void atao_reset(struct comedi_device *dev)
 
        inw(dev->iobase + ATAO_FIFO_CLEAR_REG);
 
-       devpriv->cfg1 |= ATAO_CFG1_GRP2WR;
-       outw(devpriv->cfg1, dev->iobase + ATAO_CFG1_REG);
-
+       atao_select_reg_group(dev, 1);
        outw(0, dev->iobase + ATAO_2_INT1CLR_REG);
        outw(0, dev->iobase + ATAO_2_INT2CLR_REG);
        outw(0, dev->iobase + ATAO_2_DMATCCLR_REG);
-
-       devpriv->cfg1 &= ~ATAO_CFG1_GRP2WR;
-       outw(devpriv->cfg1, dev->iobase + ATAO_CFG1_REG);
+       atao_select_reg_group(dev, 0);
 }
 
 static int atao_attach(struct comedi_device *dev, struct comedi_devconfig *it)