regulator: core: Ensure simple linear voltage mappings falls within the specified range

Integer division may truncate the result.
Use DIV_ROUND_UP to ensure simple linear voltage mappings falls within the
specified range.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/regulator/core.c

@@ -2047,7 +2047,7 @@ int regulator_map_voltage_linear(struct regulator_dev *rdev,
 		return -EINVAL;
 	}
 
-	ret = (min_uV - rdev->desc->min_uV) / rdev->desc->uV_step;
+	ret = DIV_ROUND_UP(min_uV - rdev->desc->min_uV, rdev->desc->uV_step);
 	if (ret < 0)
 		return ret;