staging: comedi: dt282x: sample types are unsigned

Sample values in comedi are generally represented as unsigned values.
Change various members of `struct dt282x_private` and various parameters
and variables dealing with samples to use `unsigned short` instead of
`short` for consistency.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/dt282x.c

@@ -226,7 +226,7 @@ struct dt282x_private {
 
 	const struct comedi_lrange *darangelist[2];
 
-	short ao[2];
+	unsigned short ao[2];
 
 	volatile int dacsr;	/* software copies of registers */
 	volatile int adcsr;
@@ -237,7 +237,7 @@ struct dt282x_private {
 
 	struct {
 		int chan;
-		short *buf;	/* DMA buffer */
+		unsigned short *buf;	/* DMA buffer */
 		volatile int size;	/* size of current transfer */
 	} dma[2];
 	int dma_maxsize;	/* max size of DMA transfer (in bytes) */
@@ -283,7 +283,7 @@ static void dt282x_disable_dma(struct comedi_device *dev);
 
 static int dt282x_grab_dma(struct comedi_device *dev, int dma1, int dma2);
 
-static void dt282x_munge(struct comedi_device *dev, short *buf,
+static void dt282x_munge(struct comedi_device *dev, unsigned short *buf,
 			 unsigned int nbytes)
 {
 	const struct dt282x_board *board = comedi_board(dev);
@@ -496,9 +496,9 @@ static irqreturn_t dt282x_interrupt(int irq, void *d)
 #if 0
 	if (adcsr & DT2821_ADDONE) {
 		int ret;
-		short data;
+		unsigned short data;
 
-		data = (short)inw(dev->iobase + DT2821_ADDAT);
+		data = inw(dev->iobase + DT2821_ADDAT);
 		data &= (1 << board->adbits) - 1;
 
 		if (devpriv->ad_2scomp)
@@ -796,7 +796,7 @@ static int dt282x_ao_insn_write(struct comedi_device *dev,
 {
 	const struct dt282x_board *board = comedi_board(dev);
 	struct dt282x_private *devpriv = dev->private;
-	short d;
+	unsigned short d;
 	unsigned int chan;
 
 	chan = CR_CHAN(insn->chanspec);