On 29/03/16 13:37, 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 82d8e5da1a33 ("iio:
> accel: bmg160: optimize transfers in trigger handler").
>
> Signed-off-by: Irina Tirdea <[email protected]>
Applied to the fixes-togreg-post-rc1 branch and marked for stable.
> ---
>
> Changes from v1:
> - pass sizeof(raw_val) to regmap_bulk_read instead of
> hardcoded value
>
> drivers/iio/gyro/bmg160_core.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/gyro/bmg160_core.c b/drivers/iio/gyro/bmg160_core.c
> index bbce3b0..8d3f0b3 100644
> --- a/drivers/iio/gyro/bmg160_core.c
> +++ b/drivers/iio/gyro/bmg160_core.c
> @@ -452,7 +452,7 @@ static int bmg160_get_temp(struct bmg160_data *data, int
> *val)
> static int bmg160_get_axis(struct bmg160_data *data, int axis, int *val)
> {
> int ret;
> - unsigned int raw_val;
> + __le16 raw_val;
>
> mutex_lock(&data->mutex);
> ret = bmg160_set_power_state(data, true);
> @@ -462,7 +462,7 @@ static int bmg160_get_axis(struct bmg160_data *data, int
> axis, int *val)
> }
>
> ret = regmap_bulk_read(data->regmap, BMG160_AXIS_TO_REG(axis), &raw_val,
> - 2);
> + sizeof(raw_val));
> if (ret < 0) {
> dev_err(data->dev, "Error reading axis %d\n", axis);
> bmg160_set_power_state(data, false);
> @@ -470,7 +470,7 @@ static int bmg160_get_axis(struct bmg160_data *data, int
> axis, int *val)
> return ret;
> }
>
> - *val = sign_extend32(raw_val, 15);
> + *val = sign_extend32(le16_to_cpu(raw_val), 15);
> ret = bmg160_set_power_state(data, false);
> mutex_unlock(&data->mutex);
> if (ret < 0)
> @@ -733,6 +733,7 @@ static const struct iio_event_spec bmg160_event = {
> .sign = 's', \
> .realbits = 16, \
> .storagebits = 16, \
> + .endianness = IIO_LE, \
> }, \
> .event_spec = &bmg160_event, \
> .num_event_specs = 1 \
>
