On Sat, 1 May 2021 18:01:18 +0100
Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
> From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
>
> 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@xxxxxxxxxx>
> Cc: Stephan Gerhold <stephan@xxxxxxxxxxx>
> Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
Applied, but with a tiny tweak to make this more obviously correct.
> ---
> drivers/iio/magnetometer/bmc150_magn.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/iio/magnetometer/bmc150_magn.c b/drivers/iio/magnetometer/bmc150_magn.c
> index 00f9766bad5c..dd5f80093a18 100644
> --- 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[4];
The whole point of the structure is to enforce the alignment without needing
to specify padding. There are only 3 actual chans, so I've reduced this to
s32 chans[3]
Result is exactly the same in practice, but it's more readable.
Thanks,
Jonathan
> + s64 timestamp __aligned(8);
> + } scan;
> struct iio_trigger *dready_trig;
> bool dready_trigger_on;
> int max_odr;
> @@ -675,11 +678,11 @@ 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:
