| Message ID | 20181204191419.144726-1-evgreen@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: adc: qcom-spmi-adc5: Initialize prescale properly | expand |
On Tue, Dec 04, 2018 at 11:14:19AM -0800, Evan Green wrote: > adc5_get_dt_data uses a local, prop, feeds it to adc5_get_dt_channel_data, > and then puts the result into adc->chan_props. The problem is > adc5_get_dt_channel_data may not initialize that structure fully, so a > garbage value is used for prescale if the optional "qcom,pre-scaling" is > not defined in DT. adc5_read_raw then uses this as an array index, > generating a crash that looks like this: > > [ 6.683186] Unable to handle kernel paging request at virtual address ffffff90e78c7964 > Call trace: > qcom_vadc_scale_code_voltage_factor+0x74/0x104 > qcom_vadc_scale_hw_calib_die_temp+0x20/0x60 > qcom_adc5_hw_scale+0x78/0xa4 > adc5_read_raw+0x3d0/0x65c > iio_channel_read+0x240/0x30c > iio_read_channel_processed+0x10c/0x150 > qpnp_tm_get_temp+0xc0/0x40c > of_thermal_get_temp+0x7c/0x98 > thermal_zone_get_temp+0xac/0xd8 > thermal_zone_device_update+0xc0/0x38c > qpnp_tm_probe+0x624/0x81c > platform_drv_probe+0xe4/0x11c > really_probe+0x188/0x3fc > driver_probe_device+0xb8/0x188 > __device_attach_driver+0x114/0x180 > bus_for_each_drv+0xd8/0x118 > __device_attach+0x180/0x27c > device_initial_probe+0x20/0x2c > bus_probe_device+0x78/0x124 > deferred_probe_work_func+0xfc/0x138 > process_one_work+0x3d8/0x8b0 > process_scheduled_works+0x48/0x6c > worker_thread+0x488/0x7cc > kthread+0x24c/0x264 > ret_from_fork+0x10/0x18 > > Unfortunately, when I went to add the initializer for this and tried to > boot it, my machine shut down immediately, complaining that it was > hotter than the sun. It appears that adc5_chans_pmic and adc5_chans_rev2 > were initializing prescale_index as if it were directly a divisor, > rather than the index into adc5_prescale_ratios that it is. > > Fix the uninitialized value, and change the static initialization to use > indices into adc5_prescale_ratios. > > Signed-off-by: Evan Green <evgreen@chromium.org> > --- > > drivers/iio/adc/qcom-spmi-adc5.c | 58 +++++++++++++++++--------------- > 1 file changed, 31 insertions(+), 27 deletions(-) > > diff --git a/drivers/iio/adc/qcom-spmi-adc5.c b/drivers/iio/adc/qcom-spmi-adc5.c > index f9af6b082916b..6a866cc187f7d 100644 > --- a/drivers/iio/adc/qcom-spmi-adc5.c > +++ b/drivers/iio/adc/qcom-spmi-adc5.c > @@ -423,6 +423,7 @@ struct adc5_channels { > enum vadc_scale_fn_type scale_fn_type; > }; > > +/* In these definitions, _pre refers to an index into adc5_prescale_ratios. */ > #define ADC5_CHAN(_dname, _type, _mask, _pre, _scale) \ > { \ > .datasheet_name = _dname, \ > @@ -443,63 +444,63 @@ struct adc5_channels { > _pre, _scale) \ > > static const struct adc5_channels adc5_chans_pmic[ADC5_MAX_CHANNEL] = { > - [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 1, > + [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 0, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 1, > + [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 0, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 3, > + [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 1, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 3, > + [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 1, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 1, > + [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 0, > SCALE_HW_CALIB_PMIC_THERM) > - [ADC5_USB_IN_I] = ADC5_CHAN_VOLT("usb_in_i_uv", 1, > + [ADC5_USB_IN_I] = ADC5_CHAN_VOLT("usb_in_i_uv", 0, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_USB_IN_V_16] = ADC5_CHAN_VOLT("usb_in_v_div_16", 16, > + [ADC5_USB_IN_V_16] = ADC5_CHAN_VOLT("usb_in_v_div_16", 8, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_CHG_TEMP] = ADC5_CHAN_TEMP("chg_temp", 1, > + [ADC5_CHG_TEMP] = ADC5_CHAN_TEMP("chg_temp", 0, > SCALE_HW_CALIB_PM5_CHG_TEMP) > /* Charger prescales SBUx and MID_CHG to fit within 1.8V upper unit */ > - [ADC5_SBUx] = ADC5_CHAN_VOLT("chg_sbux", 3, > + [ADC5_SBUx] = ADC5_CHAN_VOLT("chg_sbux", 1, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_MID_CHG_DIV6] = ADC5_CHAN_VOLT("chg_mid_chg", 6, > + [ADC5_MID_CHG_DIV6] = ADC5_CHAN_VOLT("chg_mid_chg", 3, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm", 1, > + [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm", 0, > SCALE_HW_CALIB_XOTHERM) > - [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1, > + [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0, > SCALE_HW_CALIB_THERM_100K_PULLUP) > - [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1, > + [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0, > SCALE_HW_CALIB_THERM_100K_PULLUP) > - [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1, > + [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0, > SCALE_HW_CALIB_THERM_100K_PULLUP) > - [ADC5_AMUX_THM2] = ADC5_CHAN_TEMP("amux_thm2", 1, > + [ADC5_AMUX_THM2] = ADC5_CHAN_TEMP("amux_thm2", 0, > SCALE_HW_CALIB_PM5_SMB_TEMP) > }; > > static const struct adc5_channels adc5_chans_rev2[ADC5_MAX_CHANNEL] = { > - [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 1, > + [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 0, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 1, > + [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 0, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 3, > + [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 1, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 3, > + [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 1, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_VCOIN] = ADC5_CHAN_VOLT("vcoin", 3, > + [ADC5_VCOIN] = ADC5_CHAN_VOLT("vcoin", 1, > SCALE_HW_CALIB_DEFAULT) > - [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 1, > + [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 0, > SCALE_HW_CALIB_PMIC_THERM) > - [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1, > + [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0, > SCALE_HW_CALIB_THERM_100K_PULLUP) > - [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1, > + [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0, > SCALE_HW_CALIB_THERM_100K_PULLUP) > - [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1, > + [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0, > SCALE_HW_CALIB_THERM_100K_PULLUP) > - [ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 1, > + [ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 0, > SCALE_HW_CALIB_THERM_100K_PULLUP) > - [ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 1, > + [ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 0, > SCALE_HW_CALIB_THERM_100K_PULLUP) > - [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm_100k_pu", 1, > + [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm_100k_pu", 0, > SCALE_HW_CALIB_THERM_100K_PULLUP) > }; > > @@ -558,6 +559,9 @@ static int adc5_get_dt_channel_data(struct adc5_chip *adc, > return ret; > } > prop->prescale = ret; > + } else { > + prop->prescale = > + adc->data->adc_chans[prop->channel].prescale_index; > } > > ret = of_property_read_u32(node, "qcom,hw-settle-time", &value); Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Good as an immediate fix. In the long term I wonder if it would be better to pass a ratio to ADC5_CHAN_XYZ and store it in struct adc5_channel_prop, instead of specifying the index, which is more error prone and errors are harder to spot. With this adc5_prescale_ratios would still exist, but only be used for the sanity check of prescaling values from the DT.
On Tue, 4 Dec 2018 11:57:32 -0800 Matthias Kaehlcke <mka@chromium.org> wrote: > On Tue, Dec 04, 2018 at 11:14:19AM -0800, Evan Green wrote: > > adc5_get_dt_data uses a local, prop, feeds it to adc5_get_dt_channel_data, > > and then puts the result into adc->chan_props. The problem is > > adc5_get_dt_channel_data may not initialize that structure fully, so a > > garbage value is used for prescale if the optional "qcom,pre-scaling" is > > not defined in DT. adc5_read_raw then uses this as an array index, > > generating a crash that looks like this: > > > > [ 6.683186] Unable to handle kernel paging request at virtual address ffffff90e78c7964 > > Call trace: > > qcom_vadc_scale_code_voltage_factor+0x74/0x104 > > qcom_vadc_scale_hw_calib_die_temp+0x20/0x60 > > qcom_adc5_hw_scale+0x78/0xa4 > > adc5_read_raw+0x3d0/0x65c > > iio_channel_read+0x240/0x30c > > iio_read_channel_processed+0x10c/0x150 > > qpnp_tm_get_temp+0xc0/0x40c > > of_thermal_get_temp+0x7c/0x98 > > thermal_zone_get_temp+0xac/0xd8 > > thermal_zone_device_update+0xc0/0x38c > > qpnp_tm_probe+0x624/0x81c > > platform_drv_probe+0xe4/0x11c > > really_probe+0x188/0x3fc > > driver_probe_device+0xb8/0x188 > > __device_attach_driver+0x114/0x180 > > bus_for_each_drv+0xd8/0x118 > > __device_attach+0x180/0x27c > > device_initial_probe+0x20/0x2c > > bus_probe_device+0x78/0x124 > > deferred_probe_work_func+0xfc/0x138 > > process_one_work+0x3d8/0x8b0 > > process_scheduled_works+0x48/0x6c > > worker_thread+0x488/0x7cc > > kthread+0x24c/0x264 > > ret_from_fork+0x10/0x18 > > > > Unfortunately, when I went to add the initializer for this and tried to > > boot it, my machine shut down immediately, complaining that it was > > hotter than the sun. It appears that adc5_chans_pmic and adc5_chans_rev2 > > were initializing prescale_index as if it were directly a divisor, > > rather than the index into adc5_prescale_ratios that it is. > > > > Fix the uninitialized value, and change the static initialization to use > > indices into adc5_prescale_ratios. > > > > Signed-off-by: Evan Green <evgreen@chromium.org> > > --- > > > > drivers/iio/adc/qcom-spmi-adc5.c | 58 +++++++++++++++++--------------- > > 1 file changed, 31 insertions(+), 27 deletions(-) > > > > diff --git a/drivers/iio/adc/qcom-spmi-adc5.c b/drivers/iio/adc/qcom-spmi-adc5.c > > index f9af6b082916b..6a866cc187f7d 100644 > > --- a/drivers/iio/adc/qcom-spmi-adc5.c > > +++ b/drivers/iio/adc/qcom-spmi-adc5.c > > @@ -423,6 +423,7 @@ struct adc5_channels { > > enum vadc_scale_fn_type scale_fn_type; > > }; > > > > +/* In these definitions, _pre refers to an index into adc5_prescale_ratios. */ > > #define ADC5_CHAN(_dname, _type, _mask, _pre, _scale) \ > > { \ > > .datasheet_name = _dname, \ > > @@ -443,63 +444,63 @@ struct adc5_channels { > > _pre, _scale) \ > > > > static const struct adc5_channels adc5_chans_pmic[ADC5_MAX_CHANNEL] = { > > - [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 1, > > + [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 0, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 1, > > + [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 0, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 3, > > + [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 1, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 3, > > + [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 1, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 1, > > + [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 0, > > SCALE_HW_CALIB_PMIC_THERM) > > - [ADC5_USB_IN_I] = ADC5_CHAN_VOLT("usb_in_i_uv", 1, > > + [ADC5_USB_IN_I] = ADC5_CHAN_VOLT("usb_in_i_uv", 0, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_USB_IN_V_16] = ADC5_CHAN_VOLT("usb_in_v_div_16", 16, > > + [ADC5_USB_IN_V_16] = ADC5_CHAN_VOLT("usb_in_v_div_16", 8, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_CHG_TEMP] = ADC5_CHAN_TEMP("chg_temp", 1, > > + [ADC5_CHG_TEMP] = ADC5_CHAN_TEMP("chg_temp", 0, > > SCALE_HW_CALIB_PM5_CHG_TEMP) > > /* Charger prescales SBUx and MID_CHG to fit within 1.8V upper unit */ > > - [ADC5_SBUx] = ADC5_CHAN_VOLT("chg_sbux", 3, > > + [ADC5_SBUx] = ADC5_CHAN_VOLT("chg_sbux", 1, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_MID_CHG_DIV6] = ADC5_CHAN_VOLT("chg_mid_chg", 6, > > + [ADC5_MID_CHG_DIV6] = ADC5_CHAN_VOLT("chg_mid_chg", 3, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm", 1, > > + [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm", 0, > > SCALE_HW_CALIB_XOTHERM) > > - [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1, > > + [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0, > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > - [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1, > > + [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0, > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > - [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1, > > + [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0, > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > - [ADC5_AMUX_THM2] = ADC5_CHAN_TEMP("amux_thm2", 1, > > + [ADC5_AMUX_THM2] = ADC5_CHAN_TEMP("amux_thm2", 0, > > SCALE_HW_CALIB_PM5_SMB_TEMP) > > }; > > > > static const struct adc5_channels adc5_chans_rev2[ADC5_MAX_CHANNEL] = { > > - [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 1, > > + [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 0, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 1, > > + [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 0, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 3, > > + [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 1, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 3, > > + [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 1, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_VCOIN] = ADC5_CHAN_VOLT("vcoin", 3, > > + [ADC5_VCOIN] = ADC5_CHAN_VOLT("vcoin", 1, > > SCALE_HW_CALIB_DEFAULT) > > - [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 1, > > + [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 0, > > SCALE_HW_CALIB_PMIC_THERM) > > - [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1, > > + [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0, > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > - [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1, > > + [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0, > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > - [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1, > > + [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0, > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > - [ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 1, > > + [ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 0, > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > - [ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 1, > > + [ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 0, > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > - [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm_100k_pu", 1, > > + [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm_100k_pu", 0, > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > }; > > > > @@ -558,6 +559,9 @@ static int adc5_get_dt_channel_data(struct adc5_chip *adc, > > return ret; > > } > > prop->prescale = ret; > > + } else { > > + prop->prescale = > > + adc->data->adc_chans[prop->channel].prescale_index; > > } > > > > ret = of_property_read_u32(node, "qcom,hw-settle-time", &value); > > Reviewed-by: Matthias Kaehlcke <mka@chromium.org> > > Good as an immediate fix. > > In the long term I wonder if it would be better to pass a ratio to > ADC5_CHAN_XYZ and store it in struct adc5_channel_prop, instead of > specifying the index, which is more error prone and errors are harder > to spot. With this adc5_prescale_ratios would still exist, but only be > used for the sanity check of prescaling values from the DT. I am going to let this sit for a little longer to let Siddartha have a chance to comment as well. We are getting late this cycle so this may end up going upstream at the start of the next one (as it'll be marked for stable that shouldn't matter much). Poke me if I seem to have forgotten it in a week or so. Thanks, Jonathan
On Sat, 8 Dec 2018 12:05:15 +0000 Jonathan Cameron <jic23@kernel.org> wrote: > On Tue, 4 Dec 2018 11:57:32 -0800 > Matthias Kaehlcke <mka@chromium.org> wrote: > > > On Tue, Dec 04, 2018 at 11:14:19AM -0800, Evan Green wrote: > > > adc5_get_dt_data uses a local, prop, feeds it to adc5_get_dt_channel_data, > > > and then puts the result into adc->chan_props. The problem is > > > adc5_get_dt_channel_data may not initialize that structure fully, so a > > > garbage value is used for prescale if the optional "qcom,pre-scaling" is > > > not defined in DT. adc5_read_raw then uses this as an array index, > > > generating a crash that looks like this: > > > > > > [ 6.683186] Unable to handle kernel paging request at virtual address ffffff90e78c7964 > > > Call trace: > > > qcom_vadc_scale_code_voltage_factor+0x74/0x104 > > > qcom_vadc_scale_hw_calib_die_temp+0x20/0x60 > > > qcom_adc5_hw_scale+0x78/0xa4 > > > adc5_read_raw+0x3d0/0x65c > > > iio_channel_read+0x240/0x30c > > > iio_read_channel_processed+0x10c/0x150 > > > qpnp_tm_get_temp+0xc0/0x40c > > > of_thermal_get_temp+0x7c/0x98 > > > thermal_zone_get_temp+0xac/0xd8 > > > thermal_zone_device_update+0xc0/0x38c > > > qpnp_tm_probe+0x624/0x81c > > > platform_drv_probe+0xe4/0x11c > > > really_probe+0x188/0x3fc > > > driver_probe_device+0xb8/0x188 > > > __device_attach_driver+0x114/0x180 > > > bus_for_each_drv+0xd8/0x118 > > > __device_attach+0x180/0x27c > > > device_initial_probe+0x20/0x2c > > > bus_probe_device+0x78/0x124 > > > deferred_probe_work_func+0xfc/0x138 > > > process_one_work+0x3d8/0x8b0 > > > process_scheduled_works+0x48/0x6c > > > worker_thread+0x488/0x7cc > > > kthread+0x24c/0x264 > > > ret_from_fork+0x10/0x18 > > > > > > Unfortunately, when I went to add the initializer for this and tried to > > > boot it, my machine shut down immediately, complaining that it was > > > hotter than the sun. It appears that adc5_chans_pmic and adc5_chans_rev2 > > > were initializing prescale_index as if it were directly a divisor, > > > rather than the index into adc5_prescale_ratios that it is. > > > > > > Fix the uninitialized value, and change the static initialization to use > > > indices into adc5_prescale_ratios. > > > > > > Signed-off-by: Evan Green <evgreen@chromium.org> > > > --- > > > > > > drivers/iio/adc/qcom-spmi-adc5.c | 58 +++++++++++++++++--------------- > > > 1 file changed, 31 insertions(+), 27 deletions(-) > > > > > > diff --git a/drivers/iio/adc/qcom-spmi-adc5.c b/drivers/iio/adc/qcom-spmi-adc5.c > > > index f9af6b082916b..6a866cc187f7d 100644 > > > --- a/drivers/iio/adc/qcom-spmi-adc5.c > > > +++ b/drivers/iio/adc/qcom-spmi-adc5.c > > > @@ -423,6 +423,7 @@ struct adc5_channels { > > > enum vadc_scale_fn_type scale_fn_type; > > > }; > > > > > > +/* In these definitions, _pre refers to an index into adc5_prescale_ratios. */ > > > #define ADC5_CHAN(_dname, _type, _mask, _pre, _scale) \ > > > { \ > > > .datasheet_name = _dname, \ > > > @@ -443,63 +444,63 @@ struct adc5_channels { > > > _pre, _scale) \ > > > > > > static const struct adc5_channels adc5_chans_pmic[ADC5_MAX_CHANNEL] = { > > > - [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 1, > > > + [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 0, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 1, > > > + [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 0, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 3, > > > + [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 1, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 3, > > > + [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 1, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 1, > > > + [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 0, > > > SCALE_HW_CALIB_PMIC_THERM) > > > - [ADC5_USB_IN_I] = ADC5_CHAN_VOLT("usb_in_i_uv", 1, > > > + [ADC5_USB_IN_I] = ADC5_CHAN_VOLT("usb_in_i_uv", 0, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_USB_IN_V_16] = ADC5_CHAN_VOLT("usb_in_v_div_16", 16, > > > + [ADC5_USB_IN_V_16] = ADC5_CHAN_VOLT("usb_in_v_div_16", 8, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_CHG_TEMP] = ADC5_CHAN_TEMP("chg_temp", 1, > > > + [ADC5_CHG_TEMP] = ADC5_CHAN_TEMP("chg_temp", 0, > > > SCALE_HW_CALIB_PM5_CHG_TEMP) > > > /* Charger prescales SBUx and MID_CHG to fit within 1.8V upper unit */ > > > - [ADC5_SBUx] = ADC5_CHAN_VOLT("chg_sbux", 3, > > > + [ADC5_SBUx] = ADC5_CHAN_VOLT("chg_sbux", 1, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_MID_CHG_DIV6] = ADC5_CHAN_VOLT("chg_mid_chg", 6, > > > + [ADC5_MID_CHG_DIV6] = ADC5_CHAN_VOLT("chg_mid_chg", 3, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm", 1, > > > + [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm", 0, > > > SCALE_HW_CALIB_XOTHERM) > > > - [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1, > > > + [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0, > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > - [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1, > > > + [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0, > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > - [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1, > > > + [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0, > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > - [ADC5_AMUX_THM2] = ADC5_CHAN_TEMP("amux_thm2", 1, > > > + [ADC5_AMUX_THM2] = ADC5_CHAN_TEMP("amux_thm2", 0, > > > SCALE_HW_CALIB_PM5_SMB_TEMP) > > > }; > > > > > > static const struct adc5_channels adc5_chans_rev2[ADC5_MAX_CHANNEL] = { > > > - [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 1, > > > + [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 0, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 1, > > > + [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 0, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 3, > > > + [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 1, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 3, > > > + [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 1, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_VCOIN] = ADC5_CHAN_VOLT("vcoin", 3, > > > + [ADC5_VCOIN] = ADC5_CHAN_VOLT("vcoin", 1, > > > SCALE_HW_CALIB_DEFAULT) > > > - [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 1, > > > + [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 0, > > > SCALE_HW_CALIB_PMIC_THERM) > > > - [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1, > > > + [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0, > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > - [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1, > > > + [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0, > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > - [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1, > > > + [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0, > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > - [ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 1, > > > + [ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 0, > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > - [ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 1, > > > + [ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 0, > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > - [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm_100k_pu", 1, > > > + [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm_100k_pu", 0, > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > }; > > > > > > @@ -558,6 +559,9 @@ static int adc5_get_dt_channel_data(struct adc5_chip *adc, > > > return ret; > > > } > > > prop->prescale = ret; > > > + } else { > > > + prop->prescale = > > > + adc->data->adc_chans[prop->channel].prescale_index; > > > } > > > > > > ret = of_property_read_u32(node, "qcom,hw-settle-time", &value); > > > > Reviewed-by: Matthias Kaehlcke <mka@chromium.org> > > > > Good as an immediate fix. > > > > In the long term I wonder if it would be better to pass a ratio to > > ADC5_CHAN_XYZ and store it in struct adc5_channel_prop, instead of > > specifying the index, which is more error prone and errors are harder > > to spot. With this adc5_prescale_ratios would still exist, but only be > > used for the sanity check of prescaling values from the DT. > > I am going to let this sit for a little longer to let Siddartha have > a chance to comment as well. We are getting late this cycle > so this may end up going upstream at the start of the next one > (as it'll be marked for stable that shouldn't matter much). > > Poke me if I seem to have forgotten it in a week or so. I've applied this to the togreg branch of iio.git so it'll go in during the next merge window (hopefully). Marked for stable. Thanks, Jonathan > > Thanks, > > Jonathan >
On Wed, Dec 12, 2018 at 10:41 AM Jonathan Cameron <jic23@jic23.retrosnub.co.uk> wrote: > > On Sat, 8 Dec 2018 12:05:15 +0000 > Jonathan Cameron <jic23@kernel.org> wrote: > > > On Tue, 4 Dec 2018 11:57:32 -0800 > > Matthias Kaehlcke <mka@chromium.org> wrote: > > > > > On Tue, Dec 04, 2018 at 11:14:19AM -0800, Evan Green wrote: > > > > adc5_get_dt_data uses a local, prop, feeds it to adc5_get_dt_channel_data, > > > > and then puts the result into adc->chan_props. The problem is > > > > adc5_get_dt_channel_data may not initialize that structure fully, so a > > > > garbage value is used for prescale if the optional "qcom,pre-scaling" is > > > > not defined in DT. adc5_read_raw then uses this as an array index, > > > > generating a crash that looks like this: > > > > > > > > [ 6.683186] Unable to handle kernel paging request at virtual address ffffff90e78c7964 > > > > Call trace: > > > > qcom_vadc_scale_code_voltage_factor+0x74/0x104 > > > > qcom_vadc_scale_hw_calib_die_temp+0x20/0x60 > > > > qcom_adc5_hw_scale+0x78/0xa4 > > > > adc5_read_raw+0x3d0/0x65c > > > > iio_channel_read+0x240/0x30c > > > > iio_read_channel_processed+0x10c/0x150 > > > > qpnp_tm_get_temp+0xc0/0x40c > > > > of_thermal_get_temp+0x7c/0x98 > > > > thermal_zone_get_temp+0xac/0xd8 > > > > thermal_zone_device_update+0xc0/0x38c > > > > qpnp_tm_probe+0x624/0x81c > > > > platform_drv_probe+0xe4/0x11c > > > > really_probe+0x188/0x3fc > > > > driver_probe_device+0xb8/0x188 > > > > __device_attach_driver+0x114/0x180 > > > > bus_for_each_drv+0xd8/0x118 > > > > __device_attach+0x180/0x27c > > > > device_initial_probe+0x20/0x2c > > > > bus_probe_device+0x78/0x124 > > > > deferred_probe_work_func+0xfc/0x138 > > > > process_one_work+0x3d8/0x8b0 > > > > process_scheduled_works+0x48/0x6c > > > > worker_thread+0x488/0x7cc > > > > kthread+0x24c/0x264 > > > > ret_from_fork+0x10/0x18 > > > > > > > > Unfortunately, when I went to add the initializer for this and tried to > > > > boot it, my machine shut down immediately, complaining that it was > > > > hotter than the sun. It appears that adc5_chans_pmic and adc5_chans_rev2 > > > > were initializing prescale_index as if it were directly a divisor, > > > > rather than the index into adc5_prescale_ratios that it is. > > > > > > > > Fix the uninitialized value, and change the static initialization to use > > > > indices into adc5_prescale_ratios. > > > > > > > > Signed-off-by: Evan Green <evgreen@chromium.org> > > > > --- > > > > > > > > drivers/iio/adc/qcom-spmi-adc5.c | 58 +++++++++++++++++--------------- > > > > 1 file changed, 31 insertions(+), 27 deletions(-) > > > > > > > > diff --git a/drivers/iio/adc/qcom-spmi-adc5.c b/drivers/iio/adc/qcom-spmi-adc5.c > > > > index f9af6b082916b..6a866cc187f7d 100644 > > > > --- a/drivers/iio/adc/qcom-spmi-adc5.c > > > > +++ b/drivers/iio/adc/qcom-spmi-adc5.c > > > > @@ -423,6 +423,7 @@ struct adc5_channels { > > > > enum vadc_scale_fn_type scale_fn_type; > > > > }; > > > > > > > > +/* In these definitions, _pre refers to an index into adc5_prescale_ratios. */ > > > > #define ADC5_CHAN(_dname, _type, _mask, _pre, _scale) \ > > > > { \ > > > > .datasheet_name = _dname, \ > > > > @@ -443,63 +444,63 @@ struct adc5_channels { > > > > _pre, _scale) \ > > > > > > > > static const struct adc5_channels adc5_chans_pmic[ADC5_MAX_CHANNEL] = { > > > > - [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 1, > > > > + [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 0, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 1, > > > > + [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 0, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 3, > > > > + [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 1, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 3, > > > > + [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 1, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 1, > > > > + [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 0, > > > > SCALE_HW_CALIB_PMIC_THERM) > > > > - [ADC5_USB_IN_I] = ADC5_CHAN_VOLT("usb_in_i_uv", 1, > > > > + [ADC5_USB_IN_I] = ADC5_CHAN_VOLT("usb_in_i_uv", 0, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_USB_IN_V_16] = ADC5_CHAN_VOLT("usb_in_v_div_16", 16, > > > > + [ADC5_USB_IN_V_16] = ADC5_CHAN_VOLT("usb_in_v_div_16", 8, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_CHG_TEMP] = ADC5_CHAN_TEMP("chg_temp", 1, > > > > + [ADC5_CHG_TEMP] = ADC5_CHAN_TEMP("chg_temp", 0, > > > > SCALE_HW_CALIB_PM5_CHG_TEMP) > > > > /* Charger prescales SBUx and MID_CHG to fit within 1.8V upper unit */ > > > > - [ADC5_SBUx] = ADC5_CHAN_VOLT("chg_sbux", 3, > > > > + [ADC5_SBUx] = ADC5_CHAN_VOLT("chg_sbux", 1, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_MID_CHG_DIV6] = ADC5_CHAN_VOLT("chg_mid_chg", 6, > > > > + [ADC5_MID_CHG_DIV6] = ADC5_CHAN_VOLT("chg_mid_chg", 3, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm", 1, > > > > + [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm", 0, > > > > SCALE_HW_CALIB_XOTHERM) > > > > - [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1, > > > > + [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0, > > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > > - [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1, > > > > + [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0, > > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > > - [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1, > > > > + [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0, > > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > > - [ADC5_AMUX_THM2] = ADC5_CHAN_TEMP("amux_thm2", 1, > > > > + [ADC5_AMUX_THM2] = ADC5_CHAN_TEMP("amux_thm2", 0, > > > > SCALE_HW_CALIB_PM5_SMB_TEMP) > > > > }; > > > > > > > > static const struct adc5_channels adc5_chans_rev2[ADC5_MAX_CHANNEL] = { > > > > - [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 1, > > > > + [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 0, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 1, > > > > + [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 0, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 3, > > > > + [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 1, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 3, > > > > + [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 1, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_VCOIN] = ADC5_CHAN_VOLT("vcoin", 3, > > > > + [ADC5_VCOIN] = ADC5_CHAN_VOLT("vcoin", 1, > > > > SCALE_HW_CALIB_DEFAULT) > > > > - [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 1, > > > > + [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 0, > > > > SCALE_HW_CALIB_PMIC_THERM) > > > > - [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1, > > > > + [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0, > > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > > - [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1, > > > > + [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0, > > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > > - [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1, > > > > + [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0, > > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > > - [ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 1, > > > > + [ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 0, > > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > > - [ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 1, > > > > + [ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 0, > > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > > - [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm_100k_pu", 1, > > > > + [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm_100k_pu", 0, > > > > SCALE_HW_CALIB_THERM_100K_PULLUP) > > > > }; > > > > > > > > @@ -558,6 +559,9 @@ static int adc5_get_dt_channel_data(struct adc5_chip *adc, > > > > return ret; > > > > } > > > > prop->prescale = ret; > > > > + } else { > > > > + prop->prescale = > > > > + adc->data->adc_chans[prop->channel].prescale_index; > > > > } > > > > > > > > ret = of_property_read_u32(node, "qcom,hw-settle-time", &value); > > > > > > Reviewed-by: Matthias Kaehlcke <mka@chromium.org> > > > > > > Good as an immediate fix. > > > > > > In the long term I wonder if it would be better to pass a ratio to > > > ADC5_CHAN_XYZ and store it in struct adc5_channel_prop, instead of > > > specifying the index, which is more error prone and errors are harder > > > to spot. With this adc5_prescale_ratios would still exist, but only be > > > used for the sanity check of prescaling values from the DT. > > > > I am going to let this sit for a little longer to let Siddartha have > > a chance to comment as well. We are getting late this cycle > > so this may end up going upstream at the start of the next one > > (as it'll be marked for stable that shouldn't matter much). > > > > Poke me if I seem to have forgotten it in a week or so. > I've applied this to the togreg branch of iio.git so it'll go in > during the next merge window (hopefully). Marked for stable. > Thanks, Jonathan!
diff --git a/drivers/iio/adc/qcom-spmi-adc5.c b/drivers/iio/adc/qcom-spmi-adc5.c index f9af6b082916b..6a866cc187f7d 100644 --- a/drivers/iio/adc/qcom-spmi-adc5.c +++ b/drivers/iio/adc/qcom-spmi-adc5.c @@ -423,6 +423,7 @@ struct adc5_channels { enum vadc_scale_fn_type scale_fn_type; }; +/* In these definitions, _pre refers to an index into adc5_prescale_ratios. */ #define ADC5_CHAN(_dname, _type, _mask, _pre, _scale) \ { \ .datasheet_name = _dname, \ @@ -443,63 +444,63 @@ struct adc5_channels { _pre, _scale) \ static const struct adc5_channels adc5_chans_pmic[ADC5_MAX_CHANNEL] = { - [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 1, + [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 0, SCALE_HW_CALIB_DEFAULT) - [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 1, + [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 0, SCALE_HW_CALIB_DEFAULT) - [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 3, + [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 1, SCALE_HW_CALIB_DEFAULT) - [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 3, + [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 1, SCALE_HW_CALIB_DEFAULT) - [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 1, + [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 0, SCALE_HW_CALIB_PMIC_THERM) - [ADC5_USB_IN_I] = ADC5_CHAN_VOLT("usb_in_i_uv", 1, + [ADC5_USB_IN_I] = ADC5_CHAN_VOLT("usb_in_i_uv", 0, SCALE_HW_CALIB_DEFAULT) - [ADC5_USB_IN_V_16] = ADC5_CHAN_VOLT("usb_in_v_div_16", 16, + [ADC5_USB_IN_V_16] = ADC5_CHAN_VOLT("usb_in_v_div_16", 8, SCALE_HW_CALIB_DEFAULT) - [ADC5_CHG_TEMP] = ADC5_CHAN_TEMP("chg_temp", 1, + [ADC5_CHG_TEMP] = ADC5_CHAN_TEMP("chg_temp", 0, SCALE_HW_CALIB_PM5_CHG_TEMP) /* Charger prescales SBUx and MID_CHG to fit within 1.8V upper unit */ - [ADC5_SBUx] = ADC5_CHAN_VOLT("chg_sbux", 3, + [ADC5_SBUx] = ADC5_CHAN_VOLT("chg_sbux", 1, SCALE_HW_CALIB_DEFAULT) - [ADC5_MID_CHG_DIV6] = ADC5_CHAN_VOLT("chg_mid_chg", 6, + [ADC5_MID_CHG_DIV6] = ADC5_CHAN_VOLT("chg_mid_chg", 3, SCALE_HW_CALIB_DEFAULT) - [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm", 1, + [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm", 0, SCALE_HW_CALIB_XOTHERM) - [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1, + [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0, SCALE_HW_CALIB_THERM_100K_PULLUP) - [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1, + [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0, SCALE_HW_CALIB_THERM_100K_PULLUP) - [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1, + [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0, SCALE_HW_CALIB_THERM_100K_PULLUP) - [ADC5_AMUX_THM2] = ADC5_CHAN_TEMP("amux_thm2", 1, + [ADC5_AMUX_THM2] = ADC5_CHAN_TEMP("amux_thm2", 0, SCALE_HW_CALIB_PM5_SMB_TEMP) }; static const struct adc5_channels adc5_chans_rev2[ADC5_MAX_CHANNEL] = { - [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 1, + [ADC5_REF_GND] = ADC5_CHAN_VOLT("ref_gnd", 0, SCALE_HW_CALIB_DEFAULT) - [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 1, + [ADC5_1P25VREF] = ADC5_CHAN_VOLT("vref_1p25", 0, SCALE_HW_CALIB_DEFAULT) - [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 3, + [ADC5_VPH_PWR] = ADC5_CHAN_VOLT("vph_pwr", 1, SCALE_HW_CALIB_DEFAULT) - [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 3, + [ADC5_VBAT_SNS] = ADC5_CHAN_VOLT("vbat_sns", 1, SCALE_HW_CALIB_DEFAULT) - [ADC5_VCOIN] = ADC5_CHAN_VOLT("vcoin", 3, + [ADC5_VCOIN] = ADC5_CHAN_VOLT("vcoin", 1, SCALE_HW_CALIB_DEFAULT) - [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 1, + [ADC5_DIE_TEMP] = ADC5_CHAN_TEMP("die_temp", 0, SCALE_HW_CALIB_PMIC_THERM) - [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1, + [ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0, SCALE_HW_CALIB_THERM_100K_PULLUP) - [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1, + [ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0, SCALE_HW_CALIB_THERM_100K_PULLUP) - [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1, + [ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0, SCALE_HW_CALIB_THERM_100K_PULLUP) - [ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 1, + [ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 0, SCALE_HW_CALIB_THERM_100K_PULLUP) - [ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 1, + [ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 0, SCALE_HW_CALIB_THERM_100K_PULLUP) - [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm_100k_pu", 1, + [ADC5_XO_THERM_100K_PU] = ADC5_CHAN_TEMP("xo_therm_100k_pu", 0, SCALE_HW_CALIB_THERM_100K_PULLUP) }; @@ -558,6 +559,9 @@ static int adc5_get_dt_channel_data(struct adc5_chip *adc, return ret; } prop->prescale = ret; + } else { + prop->prescale = + adc->data->adc_chans[prop->channel].prescale_index; } ret = of_property_read_u32(node, "qcom,hw-settle-time", &value);
adc5_get_dt_data uses a local, prop, feeds it to adc5_get_dt_channel_data, and then puts the result into adc->chan_props. The problem is adc5_get_dt_channel_data may not initialize that structure fully, so a garbage value is used for prescale if the optional "qcom,pre-scaling" is not defined in DT. adc5_read_raw then uses this as an array index, generating a crash that looks like this: [ 6.683186] Unable to handle kernel paging request at virtual address ffffff90e78c7964 Call trace: qcom_vadc_scale_code_voltage_factor+0x74/0x104 qcom_vadc_scale_hw_calib_die_temp+0x20/0x60 qcom_adc5_hw_scale+0x78/0xa4 adc5_read_raw+0x3d0/0x65c iio_channel_read+0x240/0x30c iio_read_channel_processed+0x10c/0x150 qpnp_tm_get_temp+0xc0/0x40c of_thermal_get_temp+0x7c/0x98 thermal_zone_get_temp+0xac/0xd8 thermal_zone_device_update+0xc0/0x38c qpnp_tm_probe+0x624/0x81c platform_drv_probe+0xe4/0x11c really_probe+0x188/0x3fc driver_probe_device+0xb8/0x188 __device_attach_driver+0x114/0x180 bus_for_each_drv+0xd8/0x118 __device_attach+0x180/0x27c device_initial_probe+0x20/0x2c bus_probe_device+0x78/0x124 deferred_probe_work_func+0xfc/0x138 process_one_work+0x3d8/0x8b0 process_scheduled_works+0x48/0x6c worker_thread+0x488/0x7cc kthread+0x24c/0x264 ret_from_fork+0x10/0x18 Unfortunately, when I went to add the initializer for this and tried to boot it, my machine shut down immediately, complaining that it was hotter than the sun. It appears that adc5_chans_pmic and adc5_chans_rev2 were initializing prescale_index as if it were directly a divisor, rather than the index into adc5_prescale_ratios that it is. Fix the uninitialized value, and change the static initialization to use indices into adc5_prescale_ratios. Signed-off-by: Evan Green <evgreen@chromium.org> --- drivers/iio/adc/qcom-spmi-adc5.c | 58 +++++++++++++++++--------------- 1 file changed, 31 insertions(+), 27 deletions(-)