[PATCH 5.19 0717/1157] iio: temp: ltc2983: Fix alignment for DMA safety

From: Greg Kroah-Hartman
Date: Mon Aug 15 2022 - 20:14:40 EST


From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>

[ Upstream commit 732f2cb2fbb51bd5bc03a114bd102ab3b2f537fe ]

____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: f110f3188e56 ("iio: temperature: Add support for LTC2983")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Acked-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220508175712.647246-91-jic23@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/iio/temperature/ltc2983.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/temperature/ltc2983.c b/drivers/iio/temperature/ltc2983.c
index 4fc654275155..4b7f2b8a9758 100644
--- a/drivers/iio/temperature/ltc2983.c
+++ b/drivers/iio/temperature/ltc2983.c
@@ -204,11 +204,11 @@ struct ltc2983_data {
u8 num_channels;
u8 iio_channels;
/*
- * DMA (thus cache coherency maintenance) requires the
+ * DMA (thus cache coherency maintenance) may require the
* transfer buffers to live in their own cache lines.
* Holds the converted temperature
*/
- __be32 temp ____cacheline_aligned;
+ __be32 temp __aligned(IIO_DMA_MINALIGN);
};

struct ltc2983_sensor {
--
2.35.1