[PATCH 6.6 085/105] iio: imu: inv_icm42600: reorganize DMA aligned buffers in structure

Greg Kroah-Hartman
2025-10-21T19:56:43Z

From: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@tdk.com>

[ Upstream commit 0c122c280e78150b0c666fb69db0000cdd1d7e0a ]

Move all DMA aligned buffers together at the end of the structure.

1. Timestamp anynomous structure is not used with DMA so it doesn't
belong after __aligned(IIO_DMA_MINALIGN).
2. struct inv_icm42600_fifo contains it's own __aligned(IIO_DMA_MINALIGN)
within it at the end so it should not be after __aligned(IIO_DMA_MINALIGN)
in the outer struct either.
3. Normally 1 would have been considered a bug, but because of the extra
alignment from 2, it actually was OK, but we shouldn't be relying on such
quirks.

Signed-off-by: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@tdk.com>
Link: https://patch.msgid.link/20250630-losd-3-inv-icm42600-add-wom-support-v6-1-5bb0c84800d9@tdk.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Stable-dep-of: 466f7a2fef2a ("iio: imu: inv_icm42600: Avoid configuring if already pm_runtime suspended")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/iio/imu/inv_icm42600/inv_icm42600.h | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/iio/imu/inv_icm42600/inv_icm42600.h
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600.h
@@ -126,9 +126,9 @@ struct inv_icm42600_suspended {
* @suspended: suspended sensors configuration.
* @indio_gyro: gyroscope IIO device.
* @indio_accel: accelerometer IIO device.
- * @buffer: data transfer buffer aligned for DMA.
- * @fifo: FIFO management structure.
* @timestamp: interrupt timestamps.
+ * @fifo: FIFO management structure.
+ * @buffer: data transfer buffer aligned for DMA.
*/
struct inv_icm42600_state {
struct mutex lock;
@@ -142,12 +142,12 @@ struct inv_icm42600_state {
struct inv_icm42600_suspended suspended;
struct iio_dev *indio_gyro;
struct iio_dev *indio_accel;
- u8 buffer[2] __aligned(IIO_DMA_MINALIGN);
- struct inv_icm42600_fifo fifo;
struct {
s64 gyro;
s64 accel;
} timestamp;
+ struct inv_icm42600_fifo fifo;
+ u8 buffer[2] __aligned(IIO_DMA_MINALIGN);
};

/* Virtual register addresses: @bank on MSB (4 upper bits), @address on LSB */