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

From: Peter Ujfalusi
Date: Tue Dec 17 2019 - 05:32:41 EST


Hi Eugen,

On 17/12/2019 9.59, Eugen.Hristev@xxxxxxxxxxxxx wrote:
>
>
> 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@xxxxxx>
>> ---
>> 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.

Sorry, just sent v2 with the correct subject prefix.
By mistake I looked at the git log of at91_adc.c and picked the wrong
prefix.

>
> 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
>>
>> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
>> Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
>>

- PÃter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki