[PATCH 5.18 0668/1095] iio: potentiometer: mcp4131: Fix alignment for DMA safety

Greg Kroah-Hartman
2022-08-15T21:43:38Z

From: Jonathan Cameron <Jonathan.Cameron@huawei.com>

[ Upstream commit 4842e5de6f39ebf2c0f6da9e6a0cb751c7108507 ]

____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: 22d199a53910 ("iio: potentiometer: add driver for Microchip MCP413X/414X/415X/416X/423X/424X/425X/426X")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20220508175712.647246-85-jic23@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iio/potentiometer/mcp4131.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/potentiometer/mcp4131.c b/drivers/iio/potentiometer/mcp4131.c
index 7c8c18ab8764..7890c0993ec4 100644
--- a/drivers/iio/potentiometer/mcp4131.c
+++ b/drivers/iio/potentiometer/mcp4131.c
@@ -129,7 +129,7 @@ struct mcp4131_data {
struct spi_device *spi;
const struct mcp4131_cfg *cfg;
struct mutex lock;
- u8 buf[2] ____cacheline_aligned;
+ u8 buf[2] __aligned(IIO_DMA_MINALIGN);
};

#define MCP4131_CHANNEL(ch) { \
--
2.35.1