From: Lorenzo Bianconi lorenzo@kernel.org
commit 7762902c89c4c78d32ec562f1ada44d02039104b upstream.
st_lsm6dsx suffers of a read misalignment on untagged FIFO when all 3 supported sensors (accel, gyro and ext device) are running at different ODRs (the use-case is reported in the LSM6DSM Application Note at pag 100). Fix the issue taking into account decimation factor reading the FIFO pattern.
Fixes: e485e2a2cfd6 ("iio: imu: st_lsm6dsx: enable sensor-hub support for lsm6dsm") Signed-off-by: Lorenzo Bianconi lorenzo@kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h | 2 ++ drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c | 23 ++++++++++++++++------- 2 files changed, 18 insertions(+), 7 deletions(-)
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h @@ -337,6 +337,7 @@ enum st_lsm6dsx_fifo_mode { * @gain: Configured sensor sensitivity. * @odr: Output data rate of the sensor [Hz]. * @watermark: Sensor watermark level. + * @decimator: Sensor decimation factor. * @sip: Number of samples in a given pattern. * @ts_ref: Sensor timestamp reference for hw one. * @ext_info: Sensor settings if it is connected to i2c controller @@ -350,6 +351,7 @@ struct st_lsm6dsx_sensor { u32 odr;
u16 watermark; + u8 decimator; u8 sip; s64 ts_ref;
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c @@ -93,6 +93,7 @@ st_lsm6dsx_get_decimator_val(struct st_l break; }
+ sensor->decimator = decimator; return i == max_size ? 0 : st_lsm6dsx_decimator_table[i].val; }
@@ -337,7 +338,7 @@ static inline int st_lsm6dsx_read_block( int st_lsm6dsx_read_fifo(struct st_lsm6dsx_hw *hw) { struct st_lsm6dsx_sensor *acc_sensor, *gyro_sensor, *ext_sensor = NULL; - int err, acc_sip, gyro_sip, ts_sip, ext_sip, read_len, offset; + int err, sip, acc_sip, gyro_sip, ts_sip, ext_sip, read_len, offset; u16 fifo_len, pattern_len = hw->sip * ST_LSM6DSX_SAMPLE_SIZE; u16 fifo_diff_mask = hw->settings->fifo_ops.fifo_diff.mask; u8 gyro_buff[ST_LSM6DSX_IIO_BUFF_SIZE]; @@ -399,19 +400,20 @@ int st_lsm6dsx_read_fifo(struct st_lsm6d acc_sip = acc_sensor->sip; ts_sip = hw->ts_sip; offset = 0; + sip = 0;
while (acc_sip > 0 || gyro_sip > 0 || ext_sip > 0) { - if (gyro_sip > 0) { + if (gyro_sip > 0 && !(sip % gyro_sensor->decimator)) { memcpy(gyro_buff, &hw->buff[offset], ST_LSM6DSX_SAMPLE_SIZE); offset += ST_LSM6DSX_SAMPLE_SIZE; } - if (acc_sip > 0) { + if (acc_sip > 0 && !(sip % acc_sensor->decimator)) { memcpy(acc_buff, &hw->buff[offset], ST_LSM6DSX_SAMPLE_SIZE); offset += ST_LSM6DSX_SAMPLE_SIZE; } - if (ext_sip > 0) { + if (ext_sip > 0 && !(sip % ext_sensor->decimator)) { memcpy(ext_buff, &hw->buff[offset], ST_LSM6DSX_SAMPLE_SIZE); offset += ST_LSM6DSX_SAMPLE_SIZE; @@ -441,18 +443,25 @@ int st_lsm6dsx_read_fifo(struct st_lsm6d offset += ST_LSM6DSX_SAMPLE_SIZE; }
- if (gyro_sip-- > 0) + if (gyro_sip > 0 && !(sip % gyro_sensor->decimator)) { iio_push_to_buffers_with_timestamp( hw->iio_devs[ST_LSM6DSX_ID_GYRO], gyro_buff, gyro_sensor->ts_ref + ts); - if (acc_sip-- > 0) + gyro_sip--; + } + if (acc_sip > 0 && !(sip % acc_sensor->decimator)) { iio_push_to_buffers_with_timestamp( hw->iio_devs[ST_LSM6DSX_ID_ACC], acc_buff, acc_sensor->ts_ref + ts); - if (ext_sip-- > 0) + acc_sip--; + } + if (ext_sip > 0 && !(sip % ext_sensor->decimator)) { iio_push_to_buffers_with_timestamp( hw->iio_devs[ST_LSM6DSX_ID_EXT0], ext_buff, ext_sensor->ts_ref + ts); + ext_sip--; + } + sip++; } }