This is a note to let you know that I've just added the patch titled
iio: adc: ti-ads7950: Fix alignment for DMA safety
to the 5.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
iio-adc-ti-ads7950-fix-alignment-for-dma-safety.patch
and it can be found in the queue-5.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7b8496899acc90cdb57120381bf12ee5ddad5181
Author: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Date: Sun May 8 18:56:16 2022 +0100
iio: adc: ti-ads7950: Fix alignment for DMA safety
[ Upstream commit dd54ba8b2469f6ae665c529623a9454ce5293ca8 ]
____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.
Update the comment to include 'may'.
Fixes: 902c4b2446d4 ("iio: adc: New driver for TI ADS7950 chips")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Acked-by: David Lechner <david@xxxxxxxxxxxxxx>
Acked-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220508175712.647246-37-jic23@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/iio/adc/ti-ads7950.c b/drivers/iio/adc/ti-ads7950.c
index e3658b969c5b..2cc9a9bd9db6 100644
--- a/drivers/iio/adc/ti-ads7950.c
+++ b/drivers/iio/adc/ti-ads7950.c
@@ -102,11 +102,11 @@ struct ti_ads7950_state {
unsigned int gpio_cmd_settings_bitmask;
/*
- * DMA (thus cache coherency maintenance) requires the
+ * DMA (thus cache coherency maintenance) may require the
* transfer buffers to live in their own cache lines.
*/
u16 rx_buf[TI_ADS7950_MAX_CHAN + 2 + TI_ADS7950_TIMESTAMP_SIZE]
- ____cacheline_aligned;
+ __aligned(IIO_DMA_MINALIGN);
u16 tx_buf[TI_ADS7950_MAX_CHAN + 2];
u16 single_tx;
u16 single_rx;
