staging: comedi: das16: remove 'ai_unipolar' and 'ai_singleended'

These members in the private data are only used during the board attach.

Move the reading of the status register to the board attach and just
check the value where needed when initializing the analog input subdevice.
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>

drivers/staging/comedi/drivers/das16.c

@@ -360,8 +360,6 @@ static inline int timer_period(void)
 }
 
 struct das16_private_struct {
-	unsigned int ai_unipolar;	/*  unipolar flag */
-	unsigned int ai_singleended;	/*  single ended flag */
 	unsigned int clockbase;	/*  master clock speed in ns */
 	volatile unsigned int control_state;	/*  dma, interrupt and trigger control bits */
 	volatile unsigned long adc_byte_count;	/*  number of bytes remaining */
@@ -891,28 +889,9 @@ static void reg_dump(struct comedi_device *dev)
 static int das16_probe(struct comedi_device *dev, struct comedi_devconfig *it)
 {
 	const struct das16_board *board = comedi_board(dev);
-	struct das16_private_struct *devpriv = dev->private;
-	int status;
 	int diobits;
 
-	/* status is available on all boards */
-
-	status = inb(dev->iobase + DAS16_STATUS);
-
-	if ((status & UNIPOLAR))
-		devpriv->ai_unipolar = 1;
-	else
-		devpriv->ai_unipolar = 0;
-
-
-	if ((status & DAS16_MUXBIT))
-		devpriv->ai_singleended = 1;
-	else
-		devpriv->ai_singleended = 0;
-
-
 	/* diobits indicates boards */
-
 	diobits = inb(dev->iobase + DAS16_DIO) & 0xf0;
 
 	printk(KERN_INFO " id bits are 0x%02x\n", diobits);
@@ -976,6 +955,7 @@ static int das16_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 	struct comedi_krange *user_ai_range;
 	struct comedi_krange *user_ao_range;
 	unsigned int dma_chan = it->options[2];
+	unsigned int status;
 	int ret;
 
 	/*  check that clock setting is valid */
@@ -1091,11 +1071,13 @@ static int das16_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 	if (ret)
 		return ret;
 
+	status = inb(dev->iobase + DAS16_STATUS);
+
 	/* Analog Input subdevice */
 	s = &dev->subdevices[0];
 	s->type		= COMEDI_SUBD_AI;
 	s->subdev_flags	= SDF_READABLE;
-	if (devpriv->ai_singleended) {
+	if (status & DAS16_MUXBIT) {
 		s->subdev_flags	|= SDF_GROUND;
 		s->n_chan	= 16;
 	} else {
@@ -1106,7 +1088,7 @@ static int das16_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 	s->maxdata	= board->ai_maxdata;
 	if (devpriv->user_ai_range_table) { /*  user defined ai range */
 		s->range_table	= devpriv->user_ai_range_table;
-	} else if (devpriv->ai_unipolar) {
+	} else if (status & UNIPOLAR) {
 		s->range_table	= das16_ai_uni_lranges[board->ai_pg];
 	} else {
 		s->range_table	= das16_ai_bip_lranges[board->ai_pg];