iio: gyro: adxrs290: fix data signedness

Properly sign-extend the rate and temperature data.

Fixes: 2c8920ff ("iio: gyro: Add driver support for ADXRS290")
Signed-off-by: Kister Genesis Jimenez <kister.jimenez@analog.com>
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20211115104147.18669-1-nuno.sa@analog.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/gyro/adxrs290.c

@@ -7,6 +7,7 @@
  */
 
 #include <linux/bitfield.h>
+#include <linux/bitops.h>
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/kernel.h>
@@ -124,7 +125,7 @@ static int adxrs290_get_rate_data(struct iio_dev *indio_dev, const u8 cmd, int *
 		goto err_unlock;
 	}
 
-	*val = temp;
+	*val = sign_extend32(temp, 15);
 
 err_unlock:
 	mutex_unlock(&st->lock);
@@ -146,7 +147,7 @@ static int adxrs290_get_temp_data(struct iio_dev *indio_dev, int *val)
 	}
 
 	/* extract lower 12 bits temperature reading */
-	*val = temp & 0x0FFF;
+	*val = sign_extend32(temp, 11);
 
 err_unlock:
 	mutex_unlock(&st->lock);