> AV_CONF register (RH & TEMP. oversampling ratio's) and CTRL1 register > (ODR & BDU settings) values are lost after suspend. > > While the change in AV_CONF updates the sensor resolution modes > (overriding the user configuration before the device went to suspend); > loss of the contents of the CTRL1 register leads to failure in reading > sensor output. > > This patch restores the AV_CONF & CTRL1 registers after resume. >
Hi Shrirang, I still suspect we have some hw issue (IoT Gateway) here (cc ST folks to get more info) and anyway I guess the proposed patch will fix the issue completely since OD and HL configuration is not restored properly. Could you please double check HL/OD regs are properly preserved after resume phase? Regards, Lorenzo > Changes from v1: > - Don't drop enabling the sensor during resume > - Restore AV_CONF register along with CTRL1 > (As demonstrated with i2c register dumps of hts221 captured on Dell > IoT Gateways 300x before suspend & after resume [1]) > > Fixes: ffebe74b7c95 (iio: humidity: hts221: avoid useless ODR reconfiguration) > Signed-off-by: Shrirang Bagul <[email protected]> > > [v1] https://marc.info/?l=linux-iio&m=152506543000442&w=2 > [1] https://marc.info/?l=linux-iio&m=152534455701742&w=2 > > This patch is based on: > git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git -b testing > --- > drivers/iio/humidity/hts221_core.c | 31 +++++++++++++++++++++++++++++- > 1 file changed, 30 insertions(+), 1 deletion(-) > > diff --git a/drivers/iio/humidity/hts221_core.c > b/drivers/iio/humidity/hts221_core.c > index 166946d4978d..fc5599497f55 100644 > --- a/drivers/iio/humidity/hts221_core.c > +++ b/drivers/iio/humidity/hts221_core.c > @@ -656,14 +656,43 @@ static int __maybe_unused hts221_resume(struct device > *dev) > { > struct iio_dev *iio_dev = dev_get_drvdata(dev); > struct hts221_hw *hw = iio_priv(iio_dev); > + const struct hts221_avg *avg; > + u8 data, idx; > int err = 0; > > + /* Restore contents of AV_CONF (RH & TEMP. oversampling ratio's) */ > + avg = &hts221_avg_list[HTS221_SENSOR_H]; > + idx = hw->sensors[HTS221_SENSOR_H].cur_avg_idx; > + data = avg->avg_avl[idx]; > + err = hts221_update_avg(hw, HTS221_SENSOR_H, data); > + if (err < 0) > + goto fail_err; > + > + avg = &hts221_avg_list[HTS221_SENSOR_T]; > + idx = hw->sensors[HTS221_SENSOR_T].cur_avg_idx; > + data = avg->avg_avl[idx]; > + err = hts221_update_avg(hw, HTS221_SENSOR_T, data); > + if (err < 0) > + goto fail_err; just return err, no need for goto statement > + > + /* Restore contents of CTRL1 (BDU & ODR) */ > + err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR, > + HTS221_BDU_MASK, > + FIELD_PREP(HTS221_BDU_MASK, 1)); > + if (err < 0) > + goto fail_err; > + > + err = hts221_update_odr(hw, hw->odr); > + if (err < 0) > + goto fail_err; > + just return err, no need for goto statement > if (hw->enabled) > err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR, > HTS221_ENABLE_MASK, > FIELD_PREP(HTS221_ENABLE_MASK, > true)); > - return err; > +fail_err: > + return err < 0 ? err : 0; > } > > const struct dev_pm_ops hts221_pm_ops = { > -- > 2.17.1 >
