staging: comedi: pcl812: tidy up the analog output subdevice

For aesthetics, tidy up the analog output subdevice code.

Change the regsiter map defines to simplify the code.

Move the analog subdevice support functions out of the analog input
support functions. Tidy them up a bit during the move.

Add some whitespace to the subdevice init.
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: NIan Abbott <abbotti@mev.co.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/pcl812.c

@@ -133,11 +133,9 @@
 
 #define PCL812_TIMER_BASE			0x00
 #define PCL812_AD_LO	      4
-#define PCL812_DA1_LO	      4
 #define PCL812_AD_HI	      5
-#define PCL812_DA1_HI	      5
-#define PCL812_DA2_LO	      6
-#define PCL812_DA2_HI	      7
+#define PCL812_AO_LSB_REG(x)			(0x04 + ((x) * 2))
+#define PCL812_AO_MSB_REG(x)			(0x05 + ((x) * 2))
 #define PCL812_DI_LSB_REG			0x06
 #define PCL812_DI_MSB_REG			0x07
 #define PCL812_CLRINT	      8
@@ -697,39 +695,6 @@ static int pcl812_ai_insn_read(struct comedi_device *dev,
 	return ret ? ret : n;
 }
 
-static int pcl812_ao_insn_write(struct comedi_device *dev,
-				struct comedi_subdevice *s,
-				struct comedi_insn *insn, unsigned int *data)
-{
-	struct pcl812_private *devpriv = dev->private;
-	int chan = CR_CHAN(insn->chanspec);
-	int i;
-
-	for (i = 0; i < insn->n; i++) {
-		outb((data[i] & 0xff),
-		     dev->iobase + (chan ? PCL812_DA2_LO : PCL812_DA1_LO));
-		outb((data[i] >> 8) & 0x0f,
-		     dev->iobase + (chan ? PCL812_DA2_HI : PCL812_DA1_HI));
-		devpriv->ao_readback[chan] = data[i];
-	}
-
-	return i;
-}
-
-static int pcl812_ao_insn_read(struct comedi_device *dev,
-			       struct comedi_subdevice *s,
-			       struct comedi_insn *insn, unsigned int *data)
-{
-	struct pcl812_private *devpriv = dev->private;
-	int chan = CR_CHAN(insn->chanspec);
-	int i;
-
-	for (i = 0; i < insn->n; i++)
-		data[i] = devpriv->ao_readback[chan];
-
-	return i;
-}
-
 static int pcl812_ai_cmdtest(struct comedi_device *dev,
 			     struct comedi_subdevice *s, struct comedi_cmd *cmd)
 {
@@ -1068,6 +1033,41 @@ static int pcl812_ai_cancel(struct comedi_device *dev,
 	return 0;
 }
 
+static int pcl812_ao_insn_write(struct comedi_device *dev,
+				struct comedi_subdevice *s,
+				struct comedi_insn *insn,
+				unsigned int *data)
+{
+	struct pcl812_private *devpriv = dev->private;
+	unsigned int chan = CR_CHAN(insn->chanspec);
+	int i;
+
+	for (i = 0; i < insn->n; i++) {
+		outb((data[i] & 0xff),
+		     dev->iobase + PCL812_AO_LSB_REG(chan));
+		outb((data[i] >> 8) & 0x0f,
+		     dev->iobase + PCL812_AO_MSB_REG(chan));
+		devpriv->ao_readback[chan] = data[i];
+	}
+
+	return insn->n;
+}
+
+static int pcl812_ao_insn_read(struct comedi_device *dev,
+			       struct comedi_subdevice *s,
+			       struct comedi_insn *insn,
+			       unsigned int *data)
+{
+	struct pcl812_private *devpriv = dev->private;
+	unsigned int chan = CR_CHAN(insn->chanspec);
+	int i;
+
+	for (i = 0; i < insn->n; i++)
+		data[i] = devpriv->ao_readback[chan];
+
+	return insn->n;
+}
+
 static int pcl812_di_insn_bits(struct comedi_device *dev,
 			       struct comedi_subdevice *s,
 			       struct comedi_insn *insn,
@@ -1109,11 +1109,13 @@ static void pcl812_reset(struct comedi_device *dev)
 	case boardPCL812:
 	case boardACL8112:
 	case boardACL8216:
-		outb(0, dev->iobase + PCL812_DA2_LO);
-		outb(0, dev->iobase + PCL812_DA2_HI);
+		/* set analog output channel 1 to 0V */
+		outb(0, dev->iobase + PCL812_AO_LSB_REG(1));
+		outb(0, dev->iobase + PCL812_AO_MSB_REG(1));
 	case boardA821:
-		outb(0, dev->iobase + PCL812_DA1_LO);
-		outb(0, dev->iobase + PCL812_DA1_HI);
+		/* set analog output channel 0 to 0V */
+		outb(0, dev->iobase + PCL812_AO_LSB_REG(0));
+		outb(0, dev->iobase + PCL812_AO_MSB_REG(0));
 		pcl812_start_pacer(dev, false);
 		outb(0, dev->iobase + PCL812_DO_MSB_REG);
 		outb(0, dev->iobase + PCL812_DO_LSB_REG);
@@ -1331,13 +1333,13 @@ static int pcl812_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 	/* analog output */
 	if (board->n_aochan > 0) {
 		s = &dev->subdevices[subdev];
-		s->type = COMEDI_SUBD_AO;
-		s->subdev_flags = SDF_WRITABLE | SDF_GROUND;
-		s->n_chan = board->n_aochan;
-		s->maxdata = 0xfff;
-		s->range_table = &range_unipolar5;
-		s->insn_read = pcl812_ao_insn_read;
-		s->insn_write = pcl812_ao_insn_write;
+		s->type		= COMEDI_SUBD_AO;
+		s->subdev_flags	= SDF_WRITABLE | SDF_GROUND;
+		s->n_chan	= board->n_aochan;
+		s->maxdata	= 0xfff;
+		s->range_table	= &range_unipolar5;
+		s->insn_read	= pcl812_ao_insn_read;
+		s->insn_write	= pcl812_ao_insn_write;
 		switch (board->board_type) {
 		case boardA821:
 			if (it->options[3] == 1)