diff --git a/drivers/iio/adc/ad7124.c b/drivers/iio/adc/ad7124.c index 7b749df9eeed..b7491198e33c 100644 --- a/drivers/iio/adc/ad7124.c +++ b/drivers/iio/adc/ad7124.c @@ -807,6 +807,19 @@ static int ad7124_check_chip_id(struct ad7124_state *st) return 0; } +/* + * Input specifiers 8 - 15 are explicitly reserved for ad7124-4 + * while they are fine for ad7124-8. Values above 31 don't fit + * into the register field and so are invalid for sure. + */ +static bool ad7124_valid_input_select(unsigned int ain, const struct ad7124_chip_info *info) +{ + if (ain >= info->num_inputs && ain < 16) + return false; + + return ain <= FIELD_MAX(AD7124_CHANNEL_AINM_MSK); +} + static int ad7124_parse_channel_config(struct iio_dev *indio_dev, struct device *dev) { @@ -859,6 +872,11 @@ static int ad7124_parse_channel_config(struct iio_dev *indio_dev, if (ret) return ret; + if (!ad7124_valid_input_select(ain[0], st->chip_info) || + !ad7124_valid_input_select(ain[1], st->chip_info)) + return dev_err_probe(dev, -EINVAL, + "diff-channels property of %pfwP contains invalid data\n", child); + st->channels[channel].nr = channel; st->channels[channel].ain = AD7124_CHANNEL_AINP(ain[0]) | AD7124_CHANNEL_AINM(ain[1]);