From 62fa19bf484bfeb52c56b7c6d6a6b1222c597f9c Mon Sep 17 00:00:00 2001
From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Date: Sun, 8 May 2022 18:56:19 +0100
Subject: [PATCH] iio: adc: ti-tlc4541: Fix alignment for DMA safety
Mime-version: 1.0
Content-type: text/plain; charset=UTF-8
Content-transfer-encoding: 8bit
Git-commit: 62fa19bf484bfeb52c56b7c6d6a6b1222c597f9c
Patch-mainline: v6.0-rc1
References: git-fixes
____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: ac2bec9d587c ("iio: adc: tlc4541: add support for TI tlc4541 adc")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20220508175712.647246-40-jic23@kernel.org
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/iio/adc/ti-tlc4541.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/adc/ti-tlc4541.c b/drivers/iio/adc/ti-tlc4541.c
index 2406eda9dfc6..30f629a553a1 100644
--- a/drivers/iio/adc/ti-tlc4541.c
+++ b/drivers/iio/adc/ti-tlc4541.c
@@ -37,12 +37,12 @@ struct tlc4541_state {
struct spi_message scan_single_msg;
/*
- * DMA (thus cache coherency maintenance) requires the
+ * DMA (thus cache coherency maintenance) may require the
* transfer buffers to live in their own cache lines.
* 2 bytes data + 6 bytes padding + 8 bytes timestamp when
* call iio_push_to_buffers_with_timestamp.
*/
- __be16 rx_buf[8] ____cacheline_aligned;
+ __be16 rx_buf[8] __aligned(IIO_DMA_MINALIGN);
};
struct tlc4541_chip_info {
--
2.35.3