From db23d88756abd38e0995ea8449d0025b3de4b26b Mon Sep 17 00:00:00 2001 From: Evan Green Date: Tue, 4 Dec 2018 11:14:19 -0800 Subject: [PATCH] iio: adc: qcom-spmi-adc5: Initialize prescale properly 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 Reviewed-by: Matthias Kaehlcke Cc: Signed-off-by: Jonathan Cameron --- 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 f9af6b082916..6a866cc187f7 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); -- 2.30.2