The DAC register is 16 bits wide, so the value passed by write_raw() should be checked against that limit. Rather than hardcoding the 16-bit maximum value limit, use a define to improve readability and make the intention of the code clearer. The explicit cast is also avoided by instead explicitly checking for negative values. Suggested-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Signed-off-by: William Breathitt Gray <william.gray@xxxxxxxxxx> --- drivers/iio/addac/stx104.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/iio/addac/stx104.c b/drivers/iio/addac/stx104.c index 8730b79e921c..0ed5f71b18cb 100644 --- a/drivers/iio/addac/stx104.c +++ b/drivers/iio/addac/stx104.c @@ -13,6 +13,7 @@ #include <linux/ioport.h> #include <linux/isa.h> #include <linux/kernel.h> +#include <linux/limits.h> #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/mutex.h> @@ -181,8 +182,7 @@ static int stx104_write_raw(struct iio_dev *indio_dev, return 0; case IIO_CHAN_INFO_RAW: if (chan->output) { - /* DAC can only accept up to a 16-bit value */ - if ((unsigned int)val > 65535) + if (val < 0 || val > U16_MAX) return -EINVAL; mutex_lock(&priv->lock); -- 2.39.2