[PATCH v2 5/9] iio: imu: st_lsm6dsx: remove event_threshold field from hw struct

Francesco Lavra
2025-11-20T08:26:24Z

This field is used to store the wakeup event detection threshold value.
When adding support for more event types, some of which may have different
threshold values for different axes, storing all threshold values for all
event sources would be cumbersome. Thus, remove this field altogether, and
read the currently configured value from the sensor when requested by
userspace.

Signed-off-by: Francesco Lavra <flavra@baylibre.com>
---
drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h | 3 +--
drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 12 +++++++++---
2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
index bbb967b2754b..e727a87413e5 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
@@ -79,6 +79,7 @@ enum st_lsm6dsx_hw_id {
#define ST_LSM6DSX_MAX_TAGGED_WORD_LEN ((32 / ST_LSM6DSX_TAGGED_SAMPLE_SIZE) \
* ST_LSM6DSX_TAGGED_SAMPLE_SIZE)
#define ST_LSM6DSX_SHIFT_VAL(val, mask) (((val) << __ffs(mask)) & (mask))
+#define st_lsm6dsx_field_get(mask, reg) ((reg & mask) >> __ffs(mask))

#define ST_LSM6DSX_CHANNEL_ACC(chan_type, addr, mod, scan_idx) \
{ \
@@ -422,7 +423,6 @@ struct st_lsm6dsx_sensor {
* @sip: Total number of samples (acc/gyro/ts) in a given pattern.
* @buff: Device read buffer.
* @irq_routing: pointer to interrupt routing configuration.
- * @event_threshold: wakeup event threshold.
* @enable_event: enabled event bitmask.
* @iio_devs: Pointers to acc/gyro iio_dev instances.
* @settings: Pointer to the specific sensor settings in use.
@@ -446,7 +446,6 @@ struct st_lsm6dsx_hw {
u8 sip;

u8 irq_routing;
- u8 event_threshold;
u8 enable_event;

u8 *buff;
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
index 287a85d4bd58..117ecb080d8e 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
@@ -1900,12 +1900,20 @@ static int st_lsm6dsx_read_event(struct iio_dev *iio_dev,
{
struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);
struct st_lsm6dsx_hw *hw = sensor->hw;
+ const struct st_lsm6dsx_reg *reg;
+ u8 data;
+ int err;

if (type != IIO_EV_TYPE_THRESH)
return -EINVAL;

+ reg = &hw->settings->event_settings.sources[ST_LSM6DSX_EVENT_WAKEUP].value;
+ err = st_lsm6dsx_read_locked(hw, reg->addr, &data, sizeof(data));
+ if (err < 0)
+ return err;
+
*val2 = 0;
- *val = hw->event_threshold;
+ *val = st_lsm6dsx_field_get(reg->mask, data);

return IIO_VAL_INT;
}
@@ -1937,8 +1945,6 @@ st_lsm6dsx_write_event(struct iio_dev *iio_dev,
if (err < 0)
return -EINVAL;

- hw->event_threshold = val;
-
return 0;
}

--
2.39.5