iio:adc:ad7298: Use BIT() and GENMASK() macros

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/adc/ad7298.c

@@ -16,6 +16,7 @@
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
+#include <linux/bitops.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
@@ -25,23 +26,19 @@
 
 #include <linux/platform_data/ad7298.h>
 
-#define AD7298_WRITE	(1 << 15) /* write to the control register */
-#define AD7298_REPEAT	(1 << 14) /* repeated conversion enable */
-#define AD7298_CH(x)	(1 << (13 - (x))) /* channel select */
-#define AD7298_TSENSE	(1 << 5) /* temperature conversion enable */
-#define AD7298_EXTREF	(1 << 2) /* external reference enable */
-#define AD7298_TAVG	(1 << 1) /* temperature sensor averaging enable */
-#define AD7298_PDD	(1 << 0) /* partial power down enable */
+#define AD7298_WRITE	BIT(15) /* write to the control register */
+#define AD7298_REPEAT	BIT(14) /* repeated conversion enable */
+#define AD7298_CH(x)	BIT(13 - (x)) /* channel select */
+#define AD7298_TSENSE	BIT(5) /* temperature conversion enable */
+#define AD7298_EXTREF	BIT(2) /* external reference enable */
+#define AD7298_TAVG	BIT(1) /* temperature sensor averaging enable */
+#define AD7298_PDD	BIT(0) /* partial power down enable */
 
 #define AD7298_MAX_CHAN		8
-#define AD7298_BITS		12
-#define AD7298_STORAGE_BITS	16
 #define AD7298_INTREF_mV	2500
 
 #define AD7298_CH_TEMP		9
 
-#define RES_MASK(bits)	((1 << (bits)) - 1)
-
 struct ad7298_state {
 	struct spi_device		*spi;
 	struct regulator		*reg;
@@ -257,7 +254,7 @@ static int ad7298_read_raw(struct iio_dev *indio_dev,
 			return ret;
 
 		if (chan->address != AD7298_CH_TEMP)
-			*val = ret & RES_MASK(AD7298_BITS);
+			*val = ret & GENMASK(chan->scan_type.realbits - 1, 0);
 
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_SCALE: