iio: adc: stm32-adc: fix stopping dma

commit e6afcf6c59 upstream.

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: 2763ea0585 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Fabrice Gasnier
2019-10-25 17:04:20 +02:00
committed by Greg Kroah-Hartman
parent 78a1d6cdd3
commit a428996147

View File

@@ -1340,7 +1340,7 @@ 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;
}
@@ -1413,7 +1413,7 @@ static int stm32_adc_buffer_predisable(struct iio_dev *indio_dev)
dev_err(&indio_dev->dev, "predisable failed\n");
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");