diff options
| author | Siddartha Mohanadoss <smohanad@codeaurora.org> | 2016-09-30 16:45:28 -0700 |
|---|---|---|
| committer | Siddartha Mohanadoss <smohanad@codeaurora.org> | 2016-09-30 16:45:28 -0700 |
| commit | 03a962620b069e4571e94a267ea43cb93db27e1b (patch) | |
| tree | b8ff857b8c65885f9ed49eb85e9ca167fccf0d6b /drivers/hwmon | |
| parent | 69bf7545352dee91b2a26dea848afcede2d4eb46 (diff) | |
hwmon: qpnp-adc-common: Clamp voltage value
On VADC_HC peripheral the ADC code can extend beyond
0-0x4000 range if the input is below 0V or if the
offset and gain error needs to be calibrated out.
Clamp the values for cases where the code represents
the value below 0V.
Change-Id: I2ede3d86d812fbdf757395d92e08e70636e9965a
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>
Diffstat (limited to 'drivers/hwmon')
| -rw-r--r-- | drivers/hwmon/qpnp-adc-common.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/hwmon/qpnp-adc-common.c b/drivers/hwmon/qpnp-adc-common.c index 787a9e5a15c8..d8ef5f59edcb 100644 --- a/drivers/hwmon/qpnp-adc-common.c +++ b/drivers/hwmon/qpnp-adc-common.c @@ -39,6 +39,8 @@ #define PMI_CHG_SCALE_2 391750000000 #define QPNP_VADC_HC_VREF_CODE 0x4000 #define QPNP_VADC_HC_VDD_REFERENCE_MV 1875 +/* Clamp negative ADC code to 0 */ +#define QPNP_VADC_HC_MAX_CODE 0x7FFF /* Units for temperature below (on x axis) is in 0.1DegC as required by the battery driver. Note the resolution used @@ -752,6 +754,8 @@ int32_t qpnp_adc_scale_pmic_therm(struct qpnp_vadc_chip *vadc, if (adc_properties->adc_hc) { /* (ADC code * vref_vadc (1.875V)) / 0x4000 */ + if (adc_code > QPNP_VADC_HC_MAX_CODE) + adc_code = 0; pmic_voltage = (int64_t) adc_code; pmic_voltage *= (int64_t) (adc_properties->adc_vdd_reference * 1000); @@ -862,6 +866,8 @@ int32_t qpnp_adc_tdkntcg_therm(struct qpnp_vadc_chip *chip, if (adc_properties->adc_hc) { /* (ADC code * vref_vadc (1.875V) * 1000) / (0x4000 * 1000) */ + if (adc_code > QPNP_VADC_HC_MAX_CODE) + adc_code = 0; xo_thm_voltage = (int64_t) adc_code; xo_thm_voltage *= (int64_t) (adc_properties->adc_vdd_reference * 1000); @@ -1059,6 +1065,8 @@ int32_t qpnp_adc_scale_therm_pu2(struct qpnp_vadc_chip *chip, if (adc_properties->adc_hc) { /* (ADC code * vref_vadc (1.875V) * 1000) / (0x4000 * 1000) */ + if (adc_code > QPNP_VADC_HC_MAX_CODE) + adc_code = 0; therm_voltage = (int64_t) adc_code; therm_voltage *= (int64_t) (adc_properties->adc_vdd_reference * 1000); @@ -1094,6 +1102,8 @@ int32_t qpnp_adc_tm_scale_voltage_therm_pu2(struct qpnp_vadc_chip *chip, if (adc_properties->adc_hc) { /* (ADC code * vref_vadc (1.875V)) / 0x4000 */ + if (reg > QPNP_VADC_HC_MAX_CODE) + reg = 0; adc_voltage = (int64_t) reg; adc_voltage *= QPNP_VADC_HC_VDD_REFERENCE_MV; adc_voltage = div64_s64(adc_voltage, @@ -1228,6 +1238,8 @@ int32_t qpnp_adc_scale_default(struct qpnp_vadc_chip *vadc, if (adc_properties->adc_hc) { /* (ADC code * vref_vadc (1.875V)) / 0x4000 */ + if (adc_code > QPNP_VADC_HC_MAX_CODE) + adc_code = 0; scale_voltage = (int64_t) adc_code; scale_voltage *= (adc_properties->adc_vdd_reference * 1000); scale_voltage = div64_s64(scale_voltage, |