This is a note to let you know that I've just added the patch titled
iio: adc: max11100: Fix alignment for DMA safety
to the 5.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
iio-adc-max11100-fix-alignment-for-dma-safety.patch
and it can be found in the queue-5.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit fd307c3daaafac377818270522794f064415b546
Author: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Date: Sun May 8 18:56:04 2022 +0100
iio: adc: max11100: Fix alignment for DMA safety
[ Upstream commit 51f30d63145cc84cb8a8e0ec96f9a8b73e6b5448 ]
____cacheline_aligned is an insufficient guarantee for non-coherent DMA
on platforms with 128 byte cachelines above L1. Switch to the updated
IIO_DMA_MINALIGN definition.
Update the comment to include 'may'.
Fixes: a8e7e88df9ec ("iio: adc: Add Maxim MAX11100 driver")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Acked-by: Jacopo Mondi <jacopo@xxxxxxxxxx>
Acked-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220508175712.647246-25-jic23@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/iio/adc/max11100.c b/drivers/iio/adc/max11100.c
index eb1ce6a0315c..49e38dca8fe2 100644
--- a/drivers/iio/adc/max11100.c
+++ b/drivers/iio/adc/max11100.c
@@ -33,10 +33,10 @@ struct max11100_state {
struct spi_device *spi;
/*
- * DMA (thus cache coherency maintenance) requires the
+ * DMA (thus cache coherency maintenance) may require the
* transfer buffers to live in their own cache lines.
*/
- u8 buffer[3] ____cacheline_aligned;
+ u8 buffer[3] __aligned(IIO_DMA_MINALIGN);
};
static const struct iio_chan_spec max11100_channels[] = {
