[PATCH 5.18 0614/1095] iio: adc: ti-adc108s102: Fix alignment for DMA safety

Greg Kroah-Hartman
2022-08-15T21:38:55Z

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

[ Upstream commit 6909fe17888b66ea53ebb15640f82b97daa587a0 ]

____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.

Dual fixes tags as two cases that were introduced in different patches.
One of those patches is a fix however and likely to have been backported
to stable kernels.

Note the second alignment marking is likely to be unnecessary, but is
left for now to keep this fix simple.

Fixes: 3691e5a69449 ("iio: adc: add driver for the ti-adc084s021 chip")
Fixes: cbe5c6977604 ("iio: adc: ti-adc108s102: Fix alignment of buffer pushed to iio buffers.")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20220508175712.647246-31-jic23@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iio/adc/ti-adc108s102.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/adc/ti-adc108s102.c b/drivers/iio/adc/ti-adc108s102.c
index c8e48881c37f..c82a161630e1 100644
--- a/drivers/iio/adc/ti-adc108s102.c
+++ b/drivers/iio/adc/ti-adc108s102.c
@@ -77,8 +77,8 @@ struct adc108s102_state {
* tx_buf: 8 channel read commands, plus 1 dummy command
* rx_buf: 1 dummy response, 8 channel responses
*/
- __be16 rx_buf[9] ____cacheline_aligned;
- __be16 tx_buf[9] ____cacheline_aligned;
+ __be16 rx_buf[9] __aligned(IIO_DMA_MINALIGN);
+ __be16 tx_buf[9] __aligned(IIO_DMA_MINALIGN);
};

#define ADC108S102_V_CHAN(index) \
--
2.35.1