Re: [PATCH] iio: adc: at91: Use dma_request_chan() instead dma_request_slave_channel()

[<Eugen.Hristev@microchip.com>]

On 17.12.2019 09:50, Peter Ujfalusi wrote:

> dma_request_slave_channel() is a wrapper on top of dma_request_chan()
> eating up the error code.
> 
> By using dma_request_chan() directly the driver can support deferred
> probing against DMA.
> 
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
> ---
>   drivers/iio/adc/at91-sama5d2_adc.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)

Hi Peter,

Thank you for the patch.
Nitpick : at91 is another driver (old one for different platforms), so 
can you please change the commit oneline to iio: adc: at91-sama5d2_adc: 
to not be confused about which driver is affected.

Thanks !
Eugen

> 
> diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
> index e1850f3d5cf3..a5c7771227d5 100644
> --- a/drivers/iio/adc/at91-sama5d2_adc.c
> +++ b/drivers/iio/adc/at91-sama5d2_adc.c
> @@ -1444,10 +1444,10 @@ static void at91_adc_dma_init(struct platform_device *pdev)
>          if (st->dma_st.dma_chan)
>                  return;
> 
> -       st->dma_st.dma_chan = dma_request_slave_channel(&pdev->dev, "rx");
> -
> -       if (!st->dma_st.dma_chan)  {
> +       st->dma_st.dma_chan = dma_request_chan(&pdev->dev, "rx");
> +       if (IS_ERR(st->dma_st.dma_chan))  {
>                  dev_info(&pdev->dev, "can't get DMA channel\n");
> +               st->dma_st.dma_chan = NULL;
>                  goto dma_exit;
>          }
> 
> --
> Peter
> 
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