[PATCH 5.19 0716/1157] iio: resolver: ad2s90: Fix alignment for DMA safety

From: Greg Kroah-Hartman
Date: Mon Aug 15 2022 - 20:14:39 EST


From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>

[ Upstream commit faa05ecb1349070d874810e161b653c2220e0006 ]

____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.

Fixes tag is probably not where the issue was first introduced, but
is likely to be far beyond the point where anyone considers
backporting this fix.

Fixes: 58f08b0af857 ("staging:iio:resolver:ad2s90 general cleanup")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Acked-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220508175712.647246-90-jic23@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/iio/resolver/ad2s90.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/resolver/ad2s90.c b/drivers/iio/resolver/ad2s90.c
index d6a91f137e13..be6836e55376 100644
--- a/drivers/iio/resolver/ad2s90.c
+++ b/drivers/iio/resolver/ad2s90.c
@@ -24,7 +24,7 @@
struct ad2s90_state {
struct mutex lock; /* lock to protect rx buffer */
struct spi_device *sdev;
- u8 rx[2] ____cacheline_aligned;
+ u8 rx[2] __aligned(IIO_DMA_MINALIGN);
};

static int ad2s90_read_raw(struct iio_dev *indio_dev,
--
2.35.1