iio: imu: st_lsm6dsx: discard samples during filters settling time

During digital filters settling time the driver is expected to drop
samples since they can be corrupted. Introduce the capability to drop
a given number of samples according to the configured ODR.
Add sample_to_discard for LSM6DSM-like sensors since new generation
devices (e.g. LSM6DSO) support DRDY mask where corrupted samples are
masked in hw with values greather than 0x7ffd so the driver can easily
discard them.
I have not added sample_to_discard support for LSM6DS3 or LSM6DS3H since
I do not have any sample for testing at the moment.

Reported-by: Philippe De Muyter <phdm@macqel.be>
Tested-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/21dcd94935c147ef9b1da4984b3da6264ee9609e.1677496295.git.lorenzo@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Lorenzo Bianconi 2023-02-27 12:14:56 +01:00 committed by Jonathan Cameron
parent accb9d05df
commit db3c490503
3 changed files with 78 additions and 8 deletions

View file

@ -137,6 +137,13 @@ struct st_lsm6dsx_odr_table_entry {
int odr_len;
};
struct st_lsm6dsx_samples_to_discard {
struct {
u32 milli_hz;
u16 samples;
} val[ST_LSM6DSX_ODR_LIST_SIZE];
};
struct st_lsm6dsx_fs {
u32 gain;
u8 val;
@ -291,6 +298,7 @@ struct st_lsm6dsx_ext_dev_settings {
* @irq_config: interrupts related registers.
* @drdy_mask: register info for data-ready mask (addr + mask).
* @odr_table: Hw sensors odr table (Hz + val).
* @samples_to_discard: Number of samples to discard for filters settling time.
* @fs_table: Hw sensors gain table (gain + val).
* @decimator: List of decimator register info (addr + mask).
* @batch: List of FIFO batching register info (addr + mask).
@ -323,6 +331,7 @@ struct st_lsm6dsx_settings {
} irq_config;
struct st_lsm6dsx_reg drdy_mask;
struct st_lsm6dsx_odr_table_entry odr_table[2];
struct st_lsm6dsx_samples_to_discard samples_to_discard[2];
struct st_lsm6dsx_fs_table_entry fs_table[2];
struct st_lsm6dsx_reg decimator[ST_LSM6DSX_MAX_ID];
struct st_lsm6dsx_reg batch[ST_LSM6DSX_MAX_ID];
@ -353,6 +362,7 @@ enum st_lsm6dsx_fifo_mode {
* @hw: Pointer to instance of struct st_lsm6dsx_hw.
* @gain: Configured sensor sensitivity.
* @odr: Output data rate of the sensor [Hz].
* @samples_to_discard: Number of samples to discard for filters settling time.
* @watermark: Sensor watermark level.
* @decimator: Sensor decimation factor.
* @sip: Number of samples in a given pattern.
@ -367,6 +377,7 @@ struct st_lsm6dsx_sensor {
u32 gain;
u32 odr;
u16 samples_to_discard;
u16 watermark;
u8 decimator;
u8 sip;

View file

@ -457,17 +457,31 @@ int st_lsm6dsx_read_fifo(struct st_lsm6dsx_hw *hw)
}
if (gyro_sip > 0 && !(sip % gyro_sensor->decimator)) {
iio_push_to_buffers_with_timestamp(
hw->iio_devs[ST_LSM6DSX_ID_GYRO],
&hw->scan[ST_LSM6DSX_ID_GYRO],
gyro_sensor->ts_ref + ts);
/*
* We need to discards gyro samples during
* filters settling time
*/
if (gyro_sensor->samples_to_discard > 0)
gyro_sensor->samples_to_discard--;
else
iio_push_to_buffers_with_timestamp(
hw->iio_devs[ST_LSM6DSX_ID_GYRO],
&hw->scan[ST_LSM6DSX_ID_GYRO],
gyro_sensor->ts_ref + ts);
gyro_sip--;
}
if (acc_sip > 0 && !(sip % acc_sensor->decimator)) {
iio_push_to_buffers_with_timestamp(
hw->iio_devs[ST_LSM6DSX_ID_ACC],
&hw->scan[ST_LSM6DSX_ID_ACC],
acc_sensor->ts_ref + ts);
/*
* We need to discards accel samples during
* filters settling time
*/
if (acc_sensor->samples_to_discard > 0)
acc_sensor->samples_to_discard--;
else
iio_push_to_buffers_with_timestamp(
hw->iio_devs[ST_LSM6DSX_ID_ACC],
&hw->scan[ST_LSM6DSX_ID_ACC],
acc_sensor->ts_ref + ts);
acc_sip--;
}
if (ext_sip > 0 && !(sip % ext_sensor->decimator)) {
@ -654,6 +668,30 @@ int st_lsm6dsx_flush_fifo(struct st_lsm6dsx_hw *hw)
return err;
}
static void
st_lsm6dsx_update_samples_to_discard(struct st_lsm6dsx_sensor *sensor)
{
const struct st_lsm6dsx_samples_to_discard *data;
struct st_lsm6dsx_hw *hw = sensor->hw;
int i;
if (sensor->id != ST_LSM6DSX_ID_GYRO &&
sensor->id != ST_LSM6DSX_ID_ACC)
return;
/* check if drdy mask is supported in hw */
if (hw->settings->drdy_mask.addr)
return;
data = &hw->settings->samples_to_discard[sensor->id];
for (i = 0; i < ST_LSM6DSX_ODR_LIST_SIZE; i++) {
if (data->val[i].milli_hz == sensor->odr) {
sensor->samples_to_discard = data->val[i].samples;
return;
}
}
}
int st_lsm6dsx_update_fifo(struct st_lsm6dsx_sensor *sensor, bool enable)
{
struct st_lsm6dsx_hw *hw = sensor->hw;
@ -673,6 +711,9 @@ int st_lsm6dsx_update_fifo(struct st_lsm6dsx_sensor *sensor, bool enable)
goto out;
}
if (enable)
st_lsm6dsx_update_samples_to_discard(sensor);
err = st_lsm6dsx_device_set_enable(sensor, enable);
if (err < 0)
goto out;

View file

@ -634,6 +634,24 @@ static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
.fs_len = 4,
},
},
.samples_to_discard = {
[ST_LSM6DSX_ID_ACC] = {
.val[0] = { 12500, 1 },
.val[1] = { 26000, 1 },
.val[2] = { 52000, 1 },
.val[3] = { 104000, 2 },
.val[4] = { 208000, 2 },
.val[5] = { 416000, 2 },
},
[ST_LSM6DSX_ID_GYRO] = {
.val[0] = { 12500, 2 },
.val[1] = { 26000, 5 },
.val[2] = { 52000, 7 },
.val[3] = { 104000, 12 },
.val[4] = { 208000, 20 },
.val[5] = { 416000, 36 },
},
},
.irq_config = {
.irq1 = {
.addr = 0x0d,