iio: magn: bmc150: Fix buffer alignment in iio_push_to_buffers_with_timestamp()

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: c91746a2361d ("iio: magn: Add support for BMC150 magnetometer")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Stephan Gerhold <stephan@gerhold.net>
Cc: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210501170121.512209-17-jic23@kernel.org

diff --git a/drivers/iio/magnetometer/bmc150_magn.c b/drivers/iio/magnetometer/bmc150_magn.c
index 39920cb..5f28220 100644 (file)
--- a/drivers/iio/magnetometer/bmc150_magn.c
+++ b/drivers/iio/magnetometer/bmc150_magn.c
@@ -138,8 +138,11 @@ struct bmc150_magn_data {
        struct regmap *regmap;
        struct regulator_bulk_data regulators[2];
        struct iio_mount_matrix orientation;
-       /* 4 x 32 bits for x, y z, 4 bytes align, 64 bits timestamp */
-       s32 buffer[6];
+       /* Ensure timestamp is naturally aligned */
+       struct {
+               s32 chans[3];
+               s64 timestamp __aligned(8);
+       } scan;
        struct iio_trigger *dready_trig;
        bool dready_trigger_on;
        int max_odr;
@@ -672,11 +675,11 @@ static irqreturn_t bmc150_magn_trigger_handler(int irq, void *p)
        int ret;
 
        mutex_lock(&data->mutex);
-       ret = bmc150_magn_read_xyz(data, data->buffer);
+       ret = bmc150_magn_read_xyz(data, data->scan.chans);
        if (ret < 0)
                goto err;
 
-       iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+       iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
                                           pf->timestamp);
 
 err: