> -----Original Message-----
> From: Martin Larsson <martin.larsson@xxxxxxxx>
> Sent: 2022年7月19日 23:03
> To: Cai Huoqing <cai.huoqing@xxxxxxxxx>; Jonathan Cameron
> <jic23@xxxxxxxxxx>; linux-iio@xxxxxxxxxxxxxxx
> Cc: Martin Larsson <martin.larsson@xxxxxxxx>; Bough Chen
> <haibo.chen@xxxxxxx>; Lars-Peter Clausen <lars@xxxxxxxxxx>; Shawn Guo
> <shawnguo@xxxxxxxxxx>; Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>;
> Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>; Fabio Estevam
> <festevam@xxxxxxxxx>; dl-linux-imx <linux-imx@xxxxxxx>;
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Subject: [PATCH] iio: adc: imx8qxp-adc: propagate regulator_get_voltage error
>
> If the ADC vref regulator returns an error, for example, if CONFIG_REGULATOR
> is not set, the error will be used as a reference voltage.
>
> Introduce a guard for negative return values instead of unconditionally casting it
> to u32.
Acked-by: Haibo Chen <haibo.chen@xxxxxxx>
Regards
Haibo Chen
> ---
> drivers/iio/adc/imx8qxp-adc.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/adc/imx8qxp-adc.c b/drivers/iio/adc/imx8qxp-adc.c index
> 901dd8e1b32f..8a786d73ae8e 100644
> --- a/drivers/iio/adc/imx8qxp-adc.c
> +++ b/drivers/iio/adc/imx8qxp-adc.c
> @@ -201,7 +201,7 @@ static int imx8qxp_adc_read_raw(struct iio_dev
> *indio_dev,
> struct imx8qxp_adc *adc = iio_priv(indio_dev);
> struct device *dev = adc->dev;
>
> - u32 ctrl, vref_uv;
> + u32 ctrl;
> long ret;
>
> switch (mask) {
> @@ -244,8 +244,10 @@ static int imx8qxp_adc_read_raw(struct iio_dev
> *indio_dev,
> return IIO_VAL_INT;
>
> case IIO_CHAN_INFO_SCALE:
> - vref_uv = regulator_get_voltage(adc->vref);
> - *val = vref_uv / 1000;
> + ret = regulator_get_voltage(adc->vref);
> + if (ret < 0)
> + return ret;
> + *val = ret / 1000;
> *val2 = 12;
> return IIO_VAL_FRACTIONAL_LOG2;
>
> --
> 2.36.1
