[PATCH 5.19 0718/1157] iio: temp: max31865: Fix alignment for DMA safety

From: Greg Kroah-Hartman
Date: Mon Aug 15 2022 - 20:14:44 EST


From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>

[ Upstream commit ecdef5b8317cdf18acb46223e087f04a226fa619 ]

____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: e112dc4e18ea ("iio: temperature: Add MAX31865 RTD Support")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Cc: Navin Sankar Velliangiri <navin@xxxxxxxxxxx>
Acked-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220508175712.647246-92-jic23@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/iio/temperature/max31865.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/temperature/max31865.c b/drivers/iio/temperature/max31865.c
index e3bb78184c6e..29e23652ba5a 100644
--- a/drivers/iio/temperature/max31865.c
+++ b/drivers/iio/temperature/max31865.c
@@ -55,7 +55,7 @@ struct max31865_data {
struct mutex lock;
bool filter_50hz;
bool three_wire;
- u8 buf[2] ____cacheline_aligned;
+ u8 buf[2] __aligned(IIO_DMA_MINALIGN);
};

static int max31865_read(struct max31865_data *data, u8 reg,
--
2.35.1