diff options
Diffstat (limited to 'drivers/iio/adc/stm32-adc.c')
-rw-r--r-- | drivers/iio/adc/stm32-adc.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c index 9f63ceb15865..94fde39d9ff7 100644 --- a/drivers/iio/adc/stm32-adc.c +++ b/drivers/iio/adc/stm32-adc.c @@ -1757,15 +1757,27 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev) return 0; } -static int stm32_adc_dma_request(struct iio_dev *indio_dev) +static int stm32_adc_dma_request(struct device *dev, struct iio_dev *indio_dev) { struct stm32_adc *adc = iio_priv(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(dev, "rx"); + if (IS_ERR(adc->dma_chan)) { + ret = PTR_ERR(adc->dma_chan); + if (ret != -ENODEV) { + if (ret != -EPROBE_DEFER) + dev_err(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, @@ -1862,7 +1874,7 @@ static int stm32_adc_probe(struct platform_device *pdev) if (ret < 0) return ret; - ret = stm32_adc_dma_request(indio_dev); + ret = stm32_adc_dma_request(dev, indio_dev); if (ret < 0) return ret; |