Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit cdaedaba authored by Peter Ujfalusi's avatar Peter Ujfalusi Committed by Greg Kroah-Hartman
Browse files

iio: adc: stm32-adc: Use dma_request_chan() instead dma_request_slave_channel() 



[ Upstream commit 735404b846dffcb320264f62b76e6f70012214dd ]

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: default avatarPeter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: default avatarFabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
parent 754254da

drivers/iio/adc/stm32-adc.c

+14 −2
Original line number Diff line number Diff line
@@ -1688,9 +1688,21 @@ static int stm32_adc_dma_request(struct iio_dev *indio_dev) 
	struct dma_slave_config config;

	int ret;



	adc->dma_chan = dma_request_slave_channel(&indio_dev->dev, "rx");

	if (!adc->dma_chan)

	adc->dma_chan = dma_request_chan(&indio_dev->dev, "rx");

	if (IS_ERR(adc->dma_chan)) {

		ret = PTR_ERR(adc->dma_chan);

		if (ret != -ENODEV) {

			if (ret != -EPROBE_DEFER)

				dev_err(&indio_dev->dev,

					"DMA channel request failed with %d\n",

					ret);

			return ret;

		}



		/* DMA is optional: fall back to IRQ mode */

		adc->dma_chan = NULL;

		return 0;

	}



	adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev,

					 STM32_DMA_BUFFER_SIZE,