On 29/03/16 13:35, Irina Tirdea wrote:
> For big endian platforms, reading the axes will return
> invalid values.
>
> The device stores each axis value in a 16 bit little
> endian register. The driver uses regmap_read_bulk to get
> the axis value, resulting in a 16 bit little endian value.
> This needs to be converted to cpu endianness to work
> on big endian platforms.
>
> Fix endianness for big endian platforms by converting
> the values for the axes read from little endian to
> cpu.
>
> This is also partially fixed in commit b6fb9b6d6552 ("iio:
> accel: bmc150: optimize transfers in trigger handler").
>
> Signed-off-by: Irina Tirdea <irina.tir...@intel.com>
Applied to the fixes-togreg-post-rc1 branch of iio.git and marked for
stable.
> ---
>
> Changes from v1:
> - pass sizeof(raw_val) to regmap_bulk_read instead of
> hardcoded value
>
> drivers/iio/accel/bmc150-accel-core.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/accel/bmc150-accel-core.c
> b/drivers/iio/accel/bmc150-accel-core.c
> index c73331f7..2072a31 100644
> --- a/drivers/iio/accel/bmc150-accel-core.c
> +++ b/drivers/iio/accel/bmc150-accel-core.c
> @@ -547,7 +547,7 @@ static int bmc150_accel_get_axis(struct bmc150_accel_data
> *data,
> {
> int ret;
> int axis = chan->scan_index;
> - unsigned int raw_val;
> + __le16 raw_val;
>
> mutex_lock(&data->mutex);
> ret = bmc150_accel_set_power_state(data, true);
> @@ -557,14 +557,14 @@ static int bmc150_accel_get_axis(struct
> bmc150_accel_data *data,
> }
>
> ret = regmap_bulk_read(data->regmap, BMC150_ACCEL_AXIS_TO_REG(axis),
> - &raw_val, 2);
> + &raw_val, sizeof(raw_val));
> if (ret < 0) {
> dev_err(data->dev, "Error reading axis %d\n", axis);
> bmc150_accel_set_power_state(data, false);
> mutex_unlock(&data->mutex);
> return ret;
> }
> - *val = sign_extend32(raw_val >> chan->scan_type.shift,
> + *val = sign_extend32(le16_to_cpu(raw_val) >> chan->scan_type.shift,
> chan->scan_type.realbits - 1);
> ret = bmc150_accel_set_power_state(data, false);
> mutex_unlock(&data->mutex);
> @@ -988,6 +988,7 @@ static const struct iio_event_spec bmc150_accel_event = {
> .realbits = (bits), \
> .storagebits = 16, \
> .shift = 16 - (bits), \
> + .endianness = IIO_LE, \
> }, \
> .event_spec = &bmc150_accel_event, \
> .num_event_specs = 1 \
>
