[PATCH 5.10 459/593] iio: magn: hmc5843: Fix buffer alignment in iio_push_to_buffers_with_timestamp()

From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 03:09:30 EST


From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>

[ Upstream commit 1ef2f51e9fe424ccecca5bb0373d71b900c2cd41 ]

To make code more readable, use a structure to express the channel
layout and ensure the timestamp is 8 byte aligned.

Found during an audit of all calls of uses of
iio_push_to_buffers_with_timestamp()

Fixes: 7247645f6865 ("iio: hmc5843: Move hmc5843 out of staging")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Link: https://lore.kernel.org/r/20210501170121.512209-16-jic23@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/iio/magnetometer/hmc5843.h | 8 ++++++--
drivers/iio/magnetometer/hmc5843_core.c | 4 ++--
2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/magnetometer/hmc5843.h b/drivers/iio/magnetometer/hmc5843.h
index 3f6c0b662941..242f742f2643 100644
--- a/drivers/iio/magnetometer/hmc5843.h
+++ b/drivers/iio/magnetometer/hmc5843.h
@@ -33,7 +33,8 @@ enum hmc5843_ids {
* @lock: update and read regmap data
* @regmap: hardware access register maps
* @variant: describe chip variants
- * @buffer: 3x 16-bit channels + padding + 64-bit timestamp
+ * @scan: buffer to pack data for passing to
+ * iio_push_to_buffers_with_timestamp()
*/
struct hmc5843_data {
struct device *dev;
@@ -41,7 +42,10 @@ struct hmc5843_data {
struct regmap *regmap;
const struct hmc5843_chip_info *variant;
struct iio_mount_matrix orientation;
- __be16 buffer[8];
+ struct {
+ __be16 chans[3];
+ s64 timestamp __aligned(8);
+ } scan;
};

int hmc5843_common_probe(struct device *dev, struct regmap *regmap,
diff --git a/drivers/iio/magnetometer/hmc5843_core.c b/drivers/iio/magnetometer/hmc5843_core.c
index 780faea61d82..221563e0c18f 100644
--- a/drivers/iio/magnetometer/hmc5843_core.c
+++ b/drivers/iio/magnetometer/hmc5843_core.c
@@ -446,13 +446,13 @@ static irqreturn_t hmc5843_trigger_handler(int irq, void *p)
}

ret = regmap_bulk_read(data->regmap, HMC5843_DATA_OUT_MSB_REGS,
- data->buffer, 3 * sizeof(__be16));
+ data->scan.chans, sizeof(data->scan.chans));

mutex_unlock(&data->lock);
if (ret < 0)
goto done;

- iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+ iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
iio_get_time_ns(indio_dev));

done:
--
2.30.2