Am 11. Jänner 2020 13:15:18 MEZ schrieb Jonathan Cameron <jic23@xxxxxxxxxx>:
>On Sat, 4 Jan 2020 14:20:52 +0100
>Martin Kepplinger <martin.kepplinger@xxxxxxx> wrote:
>
>> Allow to read the mount-matrix device tree property and provide the
>> mount_matrix file for userspace to read.
>>
>> Signed-off-by: Martin Kepplinger <martin.kepplinger@xxxxxxx>
>> ---
>>
>> tested using the lsm9ds1 on the librem5-devkit (and userspace tools
>like
>> iio-sensor-proxy) where this will be needed.
>>
>> thanks,
>>
>> martin
>>
>> revision history
>> ----------------
>> v2: additions and simplifications according to Lorenzo's review.
>thanks.
>>
>>
>> drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h | 19
>+++++++++++++++++++
>> drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 2 +-
>> 2 files changed, 20 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
>b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
>> index a763ff46f596..7076fc8c4c3b 100644
>> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
>> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
>> @@ -76,6 +76,7 @@ enum st_lsm6dsx_hw_id {
>> .endianness = IIO_LE, \
>> }, \
>> .event_spec = &st_lsm6dsx_event, \
>> + .ext_info = st_lsm6dsx_accel_ext_info, \
>> .num_event_specs = 1, \
>> }
>>
>> @@ -380,6 +381,7 @@ struct st_lsm6dsx_sensor {
>> * @enable_event: enabled event bitmask.
>> * @iio_devs: Pointers to acc/gyro iio_dev instances.
>> * @settings: Pointer to the specific sensor settings in use.
>> + * @orientation: sensor chip orientation relative to main hardware.
>> */
>> struct st_lsm6dsx_hw {
>> struct device *dev;
>> @@ -406,6 +408,8 @@ struct st_lsm6dsx_hw {
>> struct iio_dev *iio_devs[ST_LSM6DSX_ID_MAX];
>>
>> const struct st_lsm6dsx_settings *settings;
>> +
>> + struct iio_mount_matrix orientation;
>> };
>>
>> static __maybe_unused const struct iio_event_spec st_lsm6dsx_event =
>{
>> @@ -479,4 +483,19 @@ st_lsm6dsx_write_locked(struct st_lsm6dsx_hw
>*hw, unsigned int addr,
>> return err;
>> }
>>
>> +static const inline struct iio_mount_matrix *
>> +st_lsm6dsx_get_mount_matrix(const struct iio_dev *iio_dev,
>> + const struct iio_chan_spec *chan)
>> +{
>> + struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);
>> + struct st_lsm6dsx_hw *hw = sensor->hw;
>> +
>> + return &hw->orientation;
>> +}
>> +
>> +static const struct iio_chan_spec_ext_info
>st_lsm6dsx_accel_ext_info[] = {
>> + IIO_MOUNT_MATRIX(IIO_SHARED_BY_ALL, st_lsm6dsx_get_mount_matrix),
>> + { }
>> +};
>> +
>> #endif /* ST_LSM6DSX_H */
>> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
>b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
>> index 0c64e35c7599..27e157f8a031 100644
>> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
>> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
>> @@ -2325,7 +2325,7 @@ int st_lsm6dsx_probe(struct device *dev, int
>irq, int hw_id,
>> (pdata && pdata->wakeup_source))
>> device_init_wakeup(dev, true);
>>
>> - return 0;
>> + return iio_read_mount_matrix(hw->dev, "mount-matrix",
>&hw->orientation);
>
>Race condition. iio_device_register has already been called by this
>point.
>Hence userspace interfaces are exposed. Userspace can read the mount
>matrix
>before it is initialized. This needs to be earlier in probe.
>
>Jonathan
ah thanks! I somehow knew this looks wrong but I was lazy. resending soon.
>
>> }
>> EXPORT_SYMBOL(st_lsm6dsx_probe);
>>
--
Sent from mobile.
