Re: [PATCH 2/5] iio: adc: stm32-dfsdm: fix data type

From: Jonathan Cameron
Date: Sat Jun 22 2019 - 05:21:35 EST


On Wed, 19 Jun 2019 15:03:48 +0200
Olivier Moysan <olivier.moysan@xxxxxx> wrote:

> Fix the data type as DFSDM raw output is complements 2,
> 24bits left aligned in a 32-bit register.
> This change does not affect AUDIO path
> - Set data as signed for IIO (as for AUDIO)
> - Set 8 bit right shift for IIO.
> The 8 LSBs bits of data contains channel info and are masked.
>
> Fixes: e2e6771c6462 ("IIO: ADC: add STM32 DFSDM sigma delta ADC support")
>
> Signed-off-by: Olivier Moysan <olivier.moysan@xxxxxx>
Applied to the togreg branch of iio.git and pushed out as testing
for the autobuilders to play with them.

Thanks,

Jonathan

> ---
> drivers/iio/adc/stm32-dfsdm-adc.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c
> index cb596f104919..6b90a40882f2 100644
> --- a/drivers/iio/adc/stm32-dfsdm-adc.c
> +++ b/drivers/iio/adc/stm32-dfsdm-adc.c
> @@ -1365,11 +1365,11 @@ static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev,
> BIT(IIO_CHAN_INFO_SAMP_FREQ);
>
> if (adc->dev_data->type == DFSDM_AUDIO) {
> - ch->scan_type.sign = 's';
> ch->ext_info = dfsdm_adc_audio_ext_info;
> } else {
> - ch->scan_type.sign = 'u';
> + ch->scan_type.shift = 8;
> }
> + ch->scan_type.sign = 's';
> ch->scan_type.realbits = 24;
> ch->scan_type.storagebits = 32;
>