On Thu, 9 Jun 2022 11:58:56 +0200
Olivier Moysan <olivier.moysan@xxxxxxxxxxx> wrote:
> If the vrefint calibration is zero, the vrefint channel output value
> cannot be computed. Currently, in such case, the raw conversion value
> is returned, which is not relevant.
> Do not expose the vrefint channel when the output value cannot be
> computed, instead.
>
> Fixes: 0e346b2cfa85 ("iio: adc: stm32-adc: add vrefint calibration support")
>
No line break here. Fixes is part of the tag block (and a pull request sent with
this gap will get rejected). Fixed up whilst applying.
> Signed-off-by: Olivier Moysan <olivier.moysan@xxxxxxxxxxx>
Applied to the fixes-togreg branch of iiogit.
I initially wondered if using -ENOENT for this was safe in that it couldn't
come from anywhere else. Looks like it is given how little this function does
so fair enough.
Thanks,
Jonathan
> ---
> drivers/iio/adc/stm32-adc.c | 27 +++++++++++++++++----------
> 1 file changed, 17 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
> index a68ecbda6480..f13c112f540f 100644
> --- a/drivers/iio/adc/stm32-adc.c
> +++ b/drivers/iio/adc/stm32-adc.c
> @@ -1365,7 +1365,7 @@ static int stm32_adc_read_raw(struct iio_dev *indio_dev,
> else
> ret = -EINVAL;
>
> - if (mask == IIO_CHAN_INFO_PROCESSED && adc->vrefint.vrefint_cal)
> + if (mask == IIO_CHAN_INFO_PROCESSED)
> *val = STM32_ADC_VREFINT_VOLTAGE * adc->vrefint.vrefint_cal / *val;
>
> iio_device_release_direct_mode(indio_dev);
> @@ -1979,10 +1979,10 @@ static int stm32_adc_populate_int_ch(struct iio_dev *indio_dev, const char *ch_n
>
> for (i = 0; i < STM32_ADC_INT_CH_NB; i++) {
> if (!strncmp(stm32_adc_ic[i].name, ch_name, STM32_ADC_CH_SZ)) {
> - adc->int_ch[i] = chan;
> -
> - if (stm32_adc_ic[i].idx != STM32_ADC_INT_CH_VREFINT)
> - continue;
> + if (stm32_adc_ic[i].idx != STM32_ADC_INT_CH_VREFINT) {
> + adc->int_ch[i] = chan;
> + break;
> + }
>
> /* Get calibration data for vrefint channel */
> ret = nvmem_cell_read_u16(&indio_dev->dev, "vrefint", &vrefint);
> @@ -1990,10 +1990,15 @@ static int stm32_adc_populate_int_ch(struct iio_dev *indio_dev, const char *ch_n
> return dev_err_probe(indio_dev->dev.parent, ret,
> "nvmem access error\n");
> }
> - if (ret == -ENOENT)
> - dev_dbg(&indio_dev->dev, "vrefint calibration not found\n");
> - else
> - adc->vrefint.vrefint_cal = vrefint;
> + if (ret == -ENOENT) {
> + dev_dbg(&indio_dev->dev, "vrefint calibration not found. Skip vrefint channel\n");
> + return ret;
> + } else if (!vrefint) {
> + dev_dbg(&indio_dev->dev, "Null vrefint calibration value. Skip vrefint channel\n");
> + return -ENOENT;
> + }
> + adc->int_ch[i] = chan;
> + adc->vrefint.vrefint_cal = vrefint;
> }
> }
>
> @@ -2030,7 +2035,9 @@ static int stm32_adc_generic_chan_init(struct iio_dev *indio_dev,
> }
> strncpy(adc->chan_name[val], name, STM32_ADC_CH_SZ);
> ret = stm32_adc_populate_int_ch(indio_dev, name, val);
> - if (ret)
> + if (ret == -ENOENT)
> + continue;
> + else if (ret)
> goto err;
> } else if (ret != -EINVAL) {
> dev_err(&indio_dev->dev, "Invalid label %d\n", ret);
