[PATCH 5.18 0596/1095] iio: adc: ad7298: Fix alignment for DMA safety

From: Greg Kroah-Hartman
Date: Mon Aug 15 2022 - 17:36:48 EST


From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>

[ Upstream commit 585c9772f883da3ac425e2e8277b2aaceb201f38 ]

____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: be7fd3b86ad2 ("iio:adc:ad7298 make the tx and rx buffers __be16")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Acked-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220508175712.647246-13-jic23@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/iio/adc/ad7298.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/adc/ad7298.c b/drivers/iio/adc/ad7298.c
index 3f4e73f7d35a..c0430f71f592 100644
--- a/drivers/iio/adc/ad7298.c
+++ b/drivers/iio/adc/ad7298.c
@@ -49,7 +49,7 @@ struct ad7298_state {
* DMA (thus cache coherency maintenance) requires the
* transfer buffers to live in their own cache lines.
*/
- __be16 rx_buf[12] ____cacheline_aligned;
+ __be16 rx_buf[12] __aligned(IIO_DMA_MINALIGN);
__be16 tx_buf[2];
};

--
2.35.1