4.20-stable review patch. If anyone has any objections, please let me know.
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From: Hans de Goede hdegoede@redhat.com
commit 2b531d71595d2b5b12782a49b23c335869e2621e upstream.
The current-source used for the battery temp-sensor (TS) is shared with the GPADC. For proper fuel-gauge and charger operation the TS current-source needs to be permanently on. But to read the GPADC we need to temporary switch the TS current-source to ondemand, so that the GPADC can use it, otherwise we will always read an all 0 value.
The switching from on to on-ondemand is not necessary when the TS current-source is off (this happens on devices which do not have a TS).
Prior to this commit there were 2 issues with our handling of the TS current-source switching:
1) We were writing hardcoded values to the ADC TS pin-ctrl register, overwriting various other unrelated bits. Specifically we were overwriting the current-source setting for the TS and GPIO0 pins, forcing it to 80ųA independent of its original setting. On a Chuwi Vi10 tablet this was causing us to get a too high adc value (due to a too high current-source) resulting in acpi_lpat_raw_to_temp() returning -ENOENT, resulting in:
ACPI Error: AE_ERROR, Returned by Handler for [UserDefinedRegion] ACPI Error: Method parse/execution failed _SB.SXP1._TMP, AE_ERROR
This commit fixes this by using regmap_update_bits to change only the relevant bits.
2) At the end of intel_xpower_pmic_get_raw_temp() we were unconditionally enabling the TS current-source even on devices where the TS-pin is not used and the current-source thus was off on entry of the function.
This commit fixes this by checking if the TS current-source is off when entering intel_xpower_pmic_get_raw_temp() and if so it is left as is.
Fixes: 58eefe2f3f53 (ACPI / PMIC: xpower: Do pinswitch ... reading GPADC) Signed-off-by: Hans de Goede hdegoede@redhat.com Acked-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Cc: 4.14+ stable@vger.kernel.org # 4.14+ Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/acpi/pmic/intel_pmic_xpower.c | 41 +++++++++++++++++++++++++++------- 1 file changed, 33 insertions(+), 8 deletions(-)
--- a/drivers/acpi/pmic/intel_pmic_xpower.c +++ b/drivers/acpi/pmic/intel_pmic_xpower.c @@ -20,8 +20,11 @@ #define GPI1_LDO_ON (3 << 0) #define GPI1_LDO_OFF (4 << 0)
-#define AXP288_ADC_TS_PIN_GPADC 0xf2 -#define AXP288_ADC_TS_PIN_ON 0xf3 +#define AXP288_ADC_TS_CURRENT_ON_OFF_MASK GENMASK(1, 0) +#define AXP288_ADC_TS_CURRENT_OFF (0 << 0) +#define AXP288_ADC_TS_CURRENT_ON_WHEN_CHARGING (1 << 0) +#define AXP288_ADC_TS_CURRENT_ON_ONDEMAND (2 << 0) +#define AXP288_ADC_TS_CURRENT_ON (3 << 0)
static struct pmic_table power_table[] = { { @@ -212,22 +215,44 @@ out: */ static int intel_xpower_pmic_get_raw_temp(struct regmap *regmap, int reg) { + int ret, adc_ts_pin_ctrl; u8 buf[2]; - int ret;
- ret = regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, - AXP288_ADC_TS_PIN_GPADC); + /* + * The current-source used for the battery temp-sensor (TS) is shared + * with the GPADC. For proper fuel-gauge and charger operation the TS + * current-source needs to be permanently on. But to read the GPADC we + * need to temporary switch the TS current-source to ondemand, so that + * the GPADC can use it, otherwise we will always read an all 0 value. + * + * Note that the switching from on to on-ondemand is not necessary + * when the TS current-source is off (this happens on devices which + * do not use the TS-pin). + */ + ret = regmap_read(regmap, AXP288_ADC_TS_PIN_CTRL, &adc_ts_pin_ctrl); if (ret) return ret;
- /* After switching to the GPADC pin give things some time to settle */ - usleep_range(6000, 10000); + if (adc_ts_pin_ctrl & AXP288_ADC_TS_CURRENT_ON_OFF_MASK) { + ret = regmap_update_bits(regmap, AXP288_ADC_TS_PIN_CTRL, + AXP288_ADC_TS_CURRENT_ON_OFF_MASK, + AXP288_ADC_TS_CURRENT_ON_ONDEMAND); + if (ret) + return ret; + + /* Wait a bit after switching the current-source */ + usleep_range(6000, 10000); + }
ret = regmap_bulk_read(regmap, AXP288_GP_ADC_H, buf, 2); if (ret == 0) ret = (buf[0] << 4) + ((buf[1] >> 4) & 0x0f);
- regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, AXP288_ADC_TS_PIN_ON); + if (adc_ts_pin_ctrl & AXP288_ADC_TS_CURRENT_ON_OFF_MASK) { + regmap_update_bits(regmap, AXP288_ADC_TS_PIN_CTRL, + AXP288_ADC_TS_CURRENT_ON_OFF_MASK, + AXP288_ADC_TS_CURRENT_ON); + }
return ret; }