On Wed, 19 Jun 2019 15:03:51 +0200
Olivier Moysan <olivier.moy...@st.com> wrote:

> Add a comment on DMA configuration for 16 bits record.
> 
> Signed-off-by: Olivier Moysan <olivier.moy...@st.com>
Applied.

Thanks,

Jonathan

> ---
>  drivers/iio/adc/stm32-dfsdm-adc.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c 
> b/drivers/iio/adc/stm32-dfsdm-adc.c
> index d855a605eab6..ee1e0569d0e1 100644
> --- a/drivers/iio/adc/stm32-dfsdm-adc.c
> +++ b/drivers/iio/adc/stm32-dfsdm-adc.c
> @@ -918,6 +918,11 @@ static void stm32_dfsdm_dma_buffer_done(void *data)
>  static int stm32_dfsdm_adc_dma_start(struct iio_dev *indio_dev)
>  {
>       struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
> +     /*
> +      * The DFSDM supports half-word transfers. However, for 16 bits record,
> +      * 4 bytes buswidth is kept, to avoid losing samples LSBs when left
> +      * shift is required.
> +      */
>       struct dma_slave_config config = {
>               .src_addr = (dma_addr_t)adc->dfsdm->phys_base,
>               .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,

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