Commit e6afcf6c authored Oct 25, 2019 by Fabrice Gasnier Committed by Jonathan Cameron Oct 27, 2019

iio: adc: stm32-adc: fix stopping dma



There maybe a race when using dmaengine_terminate_all(). The predisable
routine may call iio_triggered_buffer_predisable() prior to a pending DMA
callback.
Adopt dmaengine_terminate_sync() to ensure there's no pending DMA request
before calling iio_triggered_buffer_predisable().

Fixes: 2763ea05 ("iio: adc: stm32: add optional dma support")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

parent 6e82ae6b

drivers/iio/adc/stm32-adc.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -1399,7 +1399,7 @@ static int stm32_adc_dma_start(struct iio_dev *indio_dev)
		cookie = dmaengine_submit(desc);
		ret = dma_submit_error(cookie);
		if (ret) {
		dmaengine_terminate_all(adc->dma_chan);
		dmaengine_terminate_sync(adc->dma_chan);
		return ret;
		}

		@@ -1477,7 +1477,7 @@ static void __stm32_adc_buffer_predisable(struct iio_dev *indio_dev)
		stm32_adc_conv_irq_disable(adc);

		if (adc->dma_chan)
		dmaengine_terminate_all(adc->dma_chan);
		dmaengine_terminate_sync(adc->dma_chan);

		if (stm32_adc_set_trig(indio_dev, NULL))
		dev_err(&indio_dev->dev, "Can't clear trigger\n");