staging: comedi: multiq3: remove subdevice pointer math

Convert the comedi_subdevice access from pointer math to array
access.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/multiq3.c

@@ -204,8 +204,10 @@ static int multiq3_encoder_insn_read(struct comedi_device *dev,
 
 static void encoder_reset(struct comedi_device *dev)
 {
+	struct comedi_subdevice *s = &dev->subdevices[4];
 	int chan;
-	for (chan = 0; chan < dev->subdevices[4].n_chan; chan++) {
+
+	for (chan = 0; chan < s->n_chan; chan++) {
 		int control =
 		    MULTIQ3_CONTROL_MUST | MULTIQ3_AD_MUX_EN | (chan << 3);
 		outw(control, dev->iobase + MULTIQ3_CONTROL);
@@ -258,7 +260,7 @@ static int multiq3_attach(struct comedi_device *dev,
 	if (result < 0)
 		return result;
 
-	s = dev->subdevices + 0;
+	s = &dev->subdevices[0];
 	/* ai subdevice */
 	s->type = COMEDI_SUBD_AI;
 	s->subdev_flags = SDF_READABLE | SDF_GROUND;
@@ -267,7 +269,7 @@ static int multiq3_attach(struct comedi_device *dev,
 	s->maxdata = 0x1fff;
 	s->range_table = &range_bipolar5;
 
-	s = dev->subdevices + 1;
+	s = &dev->subdevices[1];
 	/* ao subdevice */
 	s->type = COMEDI_SUBD_AO;
 	s->subdev_flags = SDF_WRITABLE;
@@ -277,7 +279,7 @@ static int multiq3_attach(struct comedi_device *dev,
 	s->maxdata = 0xfff;
 	s->range_table = &range_bipolar5;
 
-	s = dev->subdevices + 2;
+	s = &dev->subdevices[2];
 	/* di subdevice */
 	s->type = COMEDI_SUBD_DI;
 	s->subdev_flags = SDF_READABLE;
@@ -286,7 +288,7 @@ static int multiq3_attach(struct comedi_device *dev,
 	s->maxdata = 1;
 	s->range_table = &range_digital;
 
-	s = dev->subdevices + 3;
+	s = &dev->subdevices[3];
 	/* do subdevice */
 	s->type = COMEDI_SUBD_DO;
 	s->subdev_flags = SDF_WRITABLE;
@@ -296,7 +298,7 @@ static int multiq3_attach(struct comedi_device *dev,
 	s->range_table = &range_digital;
 	s->state = 0;
 
-	s = dev->subdevices + 4;
+	s = &dev->subdevices[4];
 	/* encoder (counter) subdevice */
 	s->type = COMEDI_SUBD_COUNTER;
 	s->subdev_flags = SDF_READABLE | SDF_LSAMPL;