| Message ID | 20200722155103.979802-2-jic23@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | IIO: Fused set 1 and 2 of timestamp alignment fixes | expand |
On Wed, 22 Jul 2020 16:50:37 +0100 Jonathan Cameron <jic23@kernel.org> wrote: > From: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > iio_push_to_buffers_with_timestamp assumes 8 byte alignment which > is not guaranteed by an array of smaller elements. > > Note that whilst in this particular case the alignment forcing > of the ts element is not strictly necessary it acts as good > documentation. Doing this where not necessary should cut > down on the number of cut and paste introduced errors elsewhere. > > Reported-by: Lars-Peter Clausen <lars@metafoo.de> > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Applied to the fixes-togreg branch of iio.git and marked for stable. Thanks, Jonathan > --- > drivers/iio/accel/kxsd9.c | 16 +++++++++++----- > 1 file changed, 11 insertions(+), 5 deletions(-) > > diff --git a/drivers/iio/accel/kxsd9.c b/drivers/iio/accel/kxsd9.c > index 66b2e4cf24cf..0e18b92e2099 100644 > --- a/drivers/iio/accel/kxsd9.c > +++ b/drivers/iio/accel/kxsd9.c > @@ -209,14 +209,20 @@ static irqreturn_t kxsd9_trigger_handler(int irq, void *p) > const struct iio_poll_func *pf = p; > struct iio_dev *indio_dev = pf->indio_dev; > struct kxsd9_state *st = iio_priv(indio_dev); > + /* > + * Ensure correct positioning and alignment of timestamp. > + * No need to zero initialize as all elements written. > + */ > + struct { > + __be16 chan[4]; > + s64 ts __aligned(8); > + } hw_values; > int ret; > - /* 4 * 16bit values AND timestamp */ > - __be16 hw_values[8]; > > ret = regmap_bulk_read(st->map, > KXSD9_REG_X, > - &hw_values, > - 8); > + hw_values.chan, > + sizeof(hw_values.chan)); > if (ret) { > dev_err(st->dev, > "error reading data\n"); > @@ -224,7 +230,7 @@ static irqreturn_t kxsd9_trigger_handler(int irq, void *p) > } > > iio_push_to_buffers_with_timestamp(indio_dev, > - hw_values, > + &hw_values, > iio_get_time_ns(indio_dev)); > iio_trigger_notify_done(indio_dev->trig); >
diff --git a/drivers/iio/accel/kxsd9.c b/drivers/iio/accel/kxsd9.c index 66b2e4cf24cf..0e18b92e2099 100644 --- a/drivers/iio/accel/kxsd9.c +++ b/drivers/iio/accel/kxsd9.c @@ -209,14 +209,20 @@ static irqreturn_t kxsd9_trigger_handler(int irq, void *p) const struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct kxsd9_state *st = iio_priv(indio_dev); + /* + * Ensure correct positioning and alignment of timestamp. + * No need to zero initialize as all elements written. + */ + struct { + __be16 chan[4]; + s64 ts __aligned(8); + } hw_values; int ret; - /* 4 * 16bit values AND timestamp */ - __be16 hw_values[8]; ret = regmap_bulk_read(st->map, KXSD9_REG_X, - &hw_values, - 8); + hw_values.chan, + sizeof(hw_values.chan)); if (ret) { dev_err(st->dev, "error reading data\n"); @@ -224,7 +230,7 @@ static irqreturn_t kxsd9_trigger_handler(int irq, void *p) } iio_push_to_buffers_with_timestamp(indio_dev, - hw_values, + &hw_values, iio_get_time_ns(indio_dev)); iio_trigger_notify_done(indio_dev->trig);