// SPDX-License-Identifier: GPL-2.0+ /* * Charger Driver for Rockchip rk817 * * Copyright (c) 2021 Maya Matuszczyk <maccraft123mc@gmail.com> * * Authors: Maya Matuszczyk <maccraft123mc@gmail.com> * Chris Morgan <macromorgan@hotmail.com> */ #include <asm/unaligned.h> #include <linux/devm-helpers.h> #include <linux/mfd/rk808.h> #include <linux/irq.h> #include <linux/of.h> #include <linux/platform_device.h> #include <linux/power_supply.h> #include <linux/regmap.h> /* Charging statuses reported by hardware register */ enum rk817_charge_status { CHRG_OFF, DEAD_CHRG, TRICKLE_CHRG, CC_OR_CV_CHRG, CHARGE_FINISH, USB_OVER_VOL, BAT_TMP_ERR, BAT_TIM_ERR, }; /* * Max charging current read to/written from hardware register. * Note how highest value corresponding to 0x7 is the lowest * current, this is per the datasheet. */ enum rk817_chg_cur { CHG_1A, CHG_1_5A, CHG_2A, CHG_2_5A, CHG_2_75A, CHG_3A, CHG_3_5A, CHG_0_5A, }; struct rk817_charger { struct device *dev; struct rk808 *rk808; struct power_supply *bat_ps; struct power_supply *chg_ps; bool plugged_in; bool battery_present; /* * voltage_k and voltage_b values are used to calibrate the ADC * voltage readings. While they are documented in the BSP kernel and * datasheet as voltage_k and voltage_b, there is no further * information explaining them in more detail. */ uint32_t voltage_k; uint32_t voltage_b; /* * soc - state of charge - like the BSP this is stored as a percentage, * to the thousandth. BSP has a display state of charge (dsoc) and a * remaining state of charge (rsoc). This value will be used for both * purposes here so we don't do any fancy math to try and "smooth" the * charge and just report it as it is. Note for example an soc of 100 * is stored as 100000, an soc of 50 is stored as 50000, etc. */ int soc; /* * Capacity of battery when fully charged, equal or less than design * capacity depending upon wear. BSP kernel saves to nvram in mAh, * so this value is in mAh not the standard uAh. */ int fcc_mah; /* * Calibrate the SOC on a fully charged battery, this way we can use * the calibrated SOC value to correct for columb counter drift. */ bool soc_cal; /* Implementation specific immutable properties from device tree */ int res_div; int sleep_enter_current_ua; int sleep_filter_current_ua; int bat_charge_full_design_uah; int bat_voltage_min_design_uv; int bat_voltage_max_design_uv; /* Values updated periodically by driver for display. */ int charge_now_uah; int volt_avg_uv; int cur_avg_ua; int max_chg_cur_ua; int max_chg_volt_uv; int charge_status; int charger_input_volt_avg_uv; /* Work queue to periodically update values. */ struct delayed_work work; }; /* ADC coefficients extracted from BSP kernel */ #define ADC_TO_CURRENT(adc_value, res_div) \ (adc_value * 172 / res_div) #define CURRENT_TO_ADC(current, samp_res) \ (current * samp_res / 172) #define CHARGE_TO_ADC(capacity, res_div) \ (capacity * res_div * 3600 / 172 * 1000) #define ADC_TO_CHARGE_UAH(adc_value, res_div) \ (adc_value / 3600 * 172 / res_div) static int rk817_chg_cur_to_reg(u32 chg_cur_ma) { if (chg_cur_ma >= 3500) return CHG_3_5A; else if (chg_cur_ma >= 3000) return CHG_3A; else if (chg_cur_ma >= 2750) return CHG_2_75A; else if (chg_cur_ma >= 2500) return CHG_2_5A; else if (chg_cur_ma >= 2000) return CHG_2A; else if (chg_cur_ma >= 1500) return CHG_1_5A; else if (chg_cur_ma >= 1000) return CHG_1A; else if (chg_cur_ma >= 500) return CHG_0_5A; else return -EINVAL; } static int rk817_chg_cur_from_reg(u8 reg) { switch (reg) { case CHG_0_5A: return 500000; case CHG_1A: return 1000000; case CHG_1_5A: return 1500000; case CHG_2A: return 2000000; case CHG_2_5A: return 2500000; case CHG_2_75A: return 2750000; case CHG_3A: return 3000000; case CHG_3_5A: return 3500000; default: return -EINVAL; } } static void rk817_bat_calib_vol(struct rk817_charger *charger) { uint32_t vcalib0 = 0; uint32_t vcalib1 = 0; u8 bulk_reg[2]; /* calibrate voltage */ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_VCALIB0_H, bulk_reg, 2); vcalib0 = get_unaligned_be16(bulk_reg); regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_VCALIB1_H, bulk_reg, 2); vcalib1 = get_unaligned_be16(bulk_reg); /* values were taken from BSP kernel */ charger->voltage_k = (4025 - 2300) * 1000 / ((vcalib1 - vcalib0) ? (vcalib1 - vcalib0) : 1); charger->voltage_b = 4025 - (charger->voltage_k * vcalib1) / 1000; } static void rk817_bat_calib_cur(struct rk817_charger *charger) { u8 bulk_reg[2]; /* calibrate current */ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_IOFFSET_H, bulk_reg, 2); regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_CAL_OFFSET_H, bulk_reg, 2); } /* * note that only the fcc_mah is really used by this driver, the other values * are to ensure we can remain backwards compatible with the BSP kernel. */ static int rk817_record_battery_nvram_values(struct rk817_charger *charger) { u8 bulk_reg[3]; int ret, rsoc; /* * write the soc value to the nvram location used by the BSP kernel * for the dsoc value. */ put_unaligned_le24(charger->soc, bulk_reg); ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_R1, bulk_reg, 3); if (ret < 0) return ret; /* * write the remaining capacity in mah to the nvram location used by * the BSP kernel for the rsoc value. */ rsoc = (charger->soc * charger->fcc_mah) / 100000; put_unaligned_le24(rsoc, bulk_reg); ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_DATA0, bulk_reg, 3); if (ret < 0) return ret; /* write the fcc_mah in mAh, just as the BSP kernel does. */ put_unaligned_le24(charger->fcc_mah, bulk_reg); ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_DATA3, bulk_reg, 3); if (ret < 0) return ret; return 0; } static int rk817_bat_calib_cap(struct rk817_charger *charger) { struct rk808 *rk808 = charger->rk808; int tmp, charge_now, charge_now_adc, volt_avg; u8 bulk_reg[4]; /* Calibrate the soc and fcc on a fully charged battery */ if (charger->charge_status == CHARGE_FINISH && (!charger->soc_cal)) { /* * soc should be 100000 and columb counter should show the full * charge capacity. Note that if the device is unplugged for a * period of several days the columb counter will have a large * margin of error, so setting it back to the full charge on * a completed charge cycle should correct this (my device was * showing 33% battery after 3 days unplugged when it should * have been closer to 95% based on voltage and charge * current). */ charger->soc = 100000; charge_now_adc = CHARGE_TO_ADC(charger->fcc_mah, charger->res_div); put_unaligned_be32(charge_now_adc, bulk_reg); regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_INIT_H3, bulk_reg, 4); charger->soc_cal = 1; dev_dbg(charger->dev, "Fully charged. SOC is %d, full capacity is %d\n", charger->soc, charger->fcc_mah * 1000); } /* * The columb counter can drift up slightly, so we should correct for * it. But don't correct it until we're at 100% soc. */ if (charger->charge_status == CHARGE_FINISH && charger->soc_cal) { regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3, bulk_reg, 4); charge_now_adc = get_unaligned_be32(bulk_reg); if (charge_now_adc < 0) return charge_now_adc; charge_now = ADC_TO_CHARGE_UAH(charge_now_adc, charger->res_div); /* * Re-init columb counter with updated values to correct drift. */ if (charge_now / 1000 > charger->fcc_mah) { dev_dbg(charger->dev, "Recalibrating columb counter to %d uah\n", charge_now); /* * Order of operations matters here to ensure we keep * enough precision until the last step to keep from * making needless updates to columb counter. */ charge_now_adc = CHARGE_TO_ADC(charger->fcc_mah, charger->res_div); put_unaligned_be32(charge_now_adc, bulk_reg); regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_INIT_H3, bulk_reg, 4); } } /* * Calibrate the fully charged capacity when we previously had a full * battery (soc_cal = 1) and are now empty (at or below minimum design * voltage). If our columb counter is still positive, subtract that * from our fcc value to get a calibrated fcc, and if our columb * counter is negative add that to our fcc (but not to exceed our * design capacity). */ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_VOL_H, bulk_reg, 2); tmp = get_unaligned_be16(bulk_reg); volt_avg = (charger->voltage_k * tmp) + 1000 * charger->voltage_b; if (volt_avg <= charger->bat_voltage_min_design_uv && charger->soc_cal) { regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3, bulk_reg, 4); charge_now_adc = get_unaligned_be32(bulk_reg); charge_now = ADC_TO_CHARGE_UAH(charge_now_adc, charger->res_div); /* * Note, if charge_now is negative this will add it (what we * want) and if it's positive this will subtract (also what * we want). */ charger->fcc_mah = charger->fcc_mah - (charge_now / 1000); dev_dbg(charger->dev, "Recalibrating full charge capacity to %d uah\n", charger->fcc_mah * 1000); } /* * Set the SOC to 0 if we are below the minimum system voltage. */ if (volt_avg <= charger->bat_voltage_min_design_uv) { charger->soc = 0; charge_now_adc = CHARGE_TO_ADC(0, charger->res_div); put_unaligned_be32(charge_now_adc, bulk_reg); regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_INIT_H3, bulk_reg, 4); dev_warn(charger->dev, "Battery voltage %d below minimum voltage %d\n", volt_avg, charger->bat_voltage_min_design_uv); } rk817_record_battery_nvram_values(charger); return 0; } static void rk817_read_props(struct rk817_charger *charger) { int tmp, reg; u8 bulk_reg[4]; /* * Recalibrate voltage and current readings if we need to BSP does both * on CUR_CALIB_UPD, ignoring VOL_CALIB_UPD. Curiously enough, both * documentation and the BSP show that you perform an update if bit 7 * is 1, but you clear the status by writing a 1 to bit 7. */ regmap_read(charger->rk808->regmap, RK817_GAS_GAUGE_ADC_CONFIG1, ®); if (reg & RK817_VOL_CUR_CALIB_UPD) { rk817_bat_calib_cur(charger); rk817_bat_calib_vol(charger); regmap_write_bits(charger->rk808->regmap, RK817_GAS_GAUGE_ADC_CONFIG1, RK817_VOL_CUR_CALIB_UPD, RK817_VOL_CUR_CALIB_UPD); } /* Update reported charge. */ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3, bulk_reg, 4); tmp = get_unaligned_be32(bulk_reg); charger->charge_now_uah = ADC_TO_CHARGE_UAH(tmp, charger->res_div); if (charger->charge_now_uah < 0) charger->charge_now_uah = 0; if (charger->charge_now_uah > charger->fcc_mah * 1000) charger->charge_now_uah = charger->fcc_mah * 1000; /* Update soc based on reported charge. */ charger->soc = charger->charge_now_uah * 100 / charger->fcc_mah; /* Update reported voltage. */ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_VOL_H, bulk_reg, 2); tmp = get_unaligned_be16(bulk_reg); charger->volt_avg_uv = (charger->voltage_k * tmp) + 1000 * charger->voltage_b; /* * Update reported current. Note value from registers is a signed 16 * bit int. */ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_CUR_H, bulk_reg, 2); tmp = (short int)get_unaligned_be16(bulk_reg); charger->cur_avg_ua = ADC_TO_CURRENT(tmp, charger->res_div); /* * Update the max charge current. This value shouldn't change, but we * can read it to report what the PMIC says it is instead of simply * returning the default value. */ regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_OUT, ®); charger->max_chg_cur_ua = rk817_chg_cur_from_reg(reg & RK817_CHRG_CUR_SEL); /* * Update max charge voltage. Like the max charge current this value * shouldn't change, but we can report what the PMIC says. */ regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_OUT, ®); charger->max_chg_volt_uv = ((((reg & RK817_CHRG_VOL_SEL) >> 4) * 50000) + 4100000); /* Check if battery still present. */ regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_STS, ®); charger->battery_present = (reg & RK817_BAT_EXS); /* Get which type of charge we are using (if any). */ regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_STS, ®); charger->charge_status = (reg >> 4) & 0x07; /* * Get charger input voltage. Note that on my example hardware (an * Odroid Go Advance) the voltage of the power connector is measured * on the register labelled USB in the datasheet; I don't know if this * is how it is designed or just a quirk of the implementation. I * believe this will also measure the voltage of the USB output when in * OTG mode, if that is the case we may need to change this in the * future to return 0 if the power supply status is offline (I can't * test this with my current implementation. Also, when the voltage * should be zero sometimes the ADC still shows a single bit (which * would register as 20000uv). When this happens set it to 0. */ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_USB_VOL_H, bulk_reg, 2); reg = get_unaligned_be16(bulk_reg); if (reg > 1) { tmp = ((charger->voltage_k * reg / 1000 + charger->voltage_b) * 60 / 46); charger->charger_input_volt_avg_uv = tmp * 1000; } else { charger->charger_input_volt_avg_uv = 0; } /* Calibrate battery capacity and soc. */ rk817_bat_calib_cap(charger); } static int rk817_bat_get_prop(struct power_supply *ps, enum power_supply_property prop, union power_supply_propval *val) { struct rk817_charger *charger = power_supply_get_drvdata(ps); switch (prop) { case POWER_SUPPLY_PROP_PRESENT: val->intval = charger->battery_present; break; case POWER_SUPPLY_PROP_STATUS: if (charger->cur_avg_ua < 0) { val->intval = POWER_SUPPLY_STATUS_DISCHARGING; break; } switch (charger->charge_status) { case CHRG_OFF: val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING; break; /* * Dead charge is documented, but not explained. I never * observed it but assume it's a pre-charge for a dead * battery. */ case DEAD_CHRG: case TRICKLE_CHRG: case CC_OR_CV_CHRG: val->intval = POWER_SUPPLY_STATUS_CHARGING; break; case CHARGE_FINISH: val->intval = POWER_SUPPLY_STATUS_FULL; break; default: val->intval = POWER_SUPPLY_STATUS_UNKNOWN; return -EINVAL; } break; case POWER_SUPPLY_PROP_CHARGE_TYPE: switch (charger->charge_status) { case CHRG_OFF: case CHARGE_FINISH: val->intval = POWER_SUPPLY_CHARGE_TYPE_NONE; break; case TRICKLE_CHRG: val->intval = POWER_SUPPLY_CHARGE_TYPE_TRICKLE; break; case DEAD_CHRG: case CC_OR_CV_CHRG: val->intval = POWER_SUPPLY_CHARGE_TYPE_STANDARD; break; default: val->intval = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN; break; } break; case POWER_SUPPLY_PROP_CHARGE_FULL: val->intval = charger->fcc_mah * 1000; break; case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN: val->intval = charger->bat_charge_full_design_uah; break; case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN: val->intval = 0; break; case POWER_SUPPLY_PROP_CHARGE_NOW: val->intval = charger->charge_now_uah; break; case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN: val->intval = charger->bat_voltage_min_design_uv; break; case POWER_SUPPLY_PROP_CAPACITY: /* Add 500 so that values like 99999 are 100% not 99%. */ val->intval = (charger->soc + 500) / 1000; if (val->intval > 100) val->intval = 100; if (val->intval < 0) val->intval = 0; break; case POWER_SUPPLY_PROP_VOLTAGE_AVG: val->intval = charger->volt_avg_uv; break; case POWER_SUPPLY_PROP_CURRENT_AVG: val->intval = charger->cur_avg_ua; break; case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX: val->intval = charger->max_chg_cur_ua; break; case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX: val->intval = charger->max_chg_volt_uv; break; case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN: val->intval = charger->bat_voltage_max_design_uv; break; default: return -EINVAL; } return 0; } static int rk817_chg_get_prop(struct power_supply *ps, enum power_supply_property prop, union power_supply_propval *val) { struct rk817_charger *charger = power_supply_get_drvdata(ps); switch (prop) { case POWER_SUPPLY_PROP_ONLINE: val->intval = charger->plugged_in; break; case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN: /* max voltage from datasheet at 5.5v (default 5.0v) */ val->intval = 5500000; break; case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN: /* min voltage from datasheet at 3.8v (default 5.0v) */ val->intval = 3800000; break; case POWER_SUPPLY_PROP_VOLTAGE_AVG: val->intval = charger->charger_input_volt_avg_uv; break; /* * While it's possible that other implementations could use different * USB types, the current implementation for this PMIC (the Odroid Go * Advance) only uses a dedicated charging port with no rx/tx lines. */ case POWER_SUPPLY_PROP_USB_TYPE: val->intval = POWER_SUPPLY_USB_TYPE_DCP; break; default: return -EINVAL; } return 0; } static irqreturn_t rk817_plug_in_isr(int irq, void *cg) { struct rk817_charger *charger; charger = (struct rk817_charger *)cg; charger->plugged_in = 1; power_supply_changed(charger->chg_ps); power_supply_changed(charger->bat_ps); /* try to recalibrate capacity if we hit full charge. */ charger->soc_cal = 0; rk817_read_props(charger); dev_dbg(charger->dev, "Power Cord Inserted\n"); return IRQ_HANDLED; } static irqreturn_t rk817_plug_out_isr(int irq, void *cg) { struct rk817_charger *charger; struct rk808 *rk808; charger = (struct rk817_charger *)cg; rk808 = charger->rk808; charger->plugged_in = 0; power_supply_changed(charger->bat_ps); power_supply_changed(charger->chg_ps); /* * For some reason the bits of RK817_PMIC_CHRG_IN reset whenever the * power cord is unplugged. This was not documented in the BSP kernel * or the datasheet and only discovered by trial and error. Set minimum * USB input voltage to 4.5v and enable USB voltage input limit. */ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_VLIM_SEL, (0x05 << 4)); regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_VLIM_EN, (0x01 << 7)); /* * Set average USB input current limit to 1.5A and enable USB current * input limit. */ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_ILIM_SEL, 0x03); regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_ILIM_EN, (0x01 << 3)); rk817_read_props(charger); dev_dbg(charger->dev, "Power Cord Removed\n"); return IRQ_HANDLED; } static enum power_supply_property rk817_bat_props[] = { POWER_SUPPLY_PROP_PRESENT, POWER_SUPPLY_PROP_STATUS, POWER_SUPPLY_PROP_CHARGE_TYPE, POWER_SUPPLY_PROP_CHARGE_FULL, POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN, POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN, POWER_SUPPLY_PROP_CHARGE_NOW, POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX, POWER_SUPPLY_PROP_VOLTAGE_AVG, POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX, POWER_SUPPLY_PROP_CURRENT_AVG, POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN, POWER_SUPPLY_PROP_CAPACITY, POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN, }; static enum power_supply_property rk817_chg_props[] = { POWER_SUPPLY_PROP_ONLINE, POWER_SUPPLY_PROP_USB_TYPE, POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN, POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN, POWER_SUPPLY_PROP_VOLTAGE_AVG, }; static enum power_supply_usb_type rk817_usb_type[] = { POWER_SUPPLY_USB_TYPE_DCP, POWER_SUPPLY_USB_TYPE_UNKNOWN, }; static const struct power_supply_desc rk817_bat_desc = { .name = "rk817-battery", .type = POWER_SUPPLY_TYPE_BATTERY, .properties = rk817_bat_props, .num_properties = ARRAY_SIZE(rk817_bat_props), .get_property = rk817_bat_get_prop, }; static const struct power_supply_desc rk817_chg_desc = { .name = "rk817-charger", .type = POWER_SUPPLY_TYPE_USB, .usb_types = rk817_usb_type, .num_usb_types = ARRAY_SIZE(rk817_usb_type), .properties = rk817_chg_props, .num_properties = ARRAY_SIZE(rk817_chg_props), .get_property = rk817_chg_get_prop, }; static int rk817_read_battery_nvram_values(struct rk817_charger *charger) { u8 bulk_reg[3]; int ret; /* Read the nvram data for full charge capacity. */ ret = regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_DATA3, bulk_reg, 3); if (ret < 0) return ret; charger->fcc_mah = get_unaligned_le24(bulk_reg); /* * Sanity checking for values equal to zero or less than would be * practical for this device (BSP Kernel assumes 500mAH or less) for * practicality purposes. Also check if the value is too large and * correct it. */ if ((charger->fcc_mah < 500) || ((charger->fcc_mah * 1000) > charger->bat_charge_full_design_uah)) { dev_info(charger->dev, "Invalid NVRAM max charge, setting to %u uAH\n", charger->bat_charge_full_design_uah); charger->fcc_mah = charger->bat_charge_full_design_uah / 1000; } /* * Read the nvram for state of charge. Sanity check for values greater * than 100 (10000) or less than 0, because other things (BSP kernels, * U-Boot, or even i2cset) can write to this register. If the value is * off it should get corrected automatically when the voltage drops to * the min (soc is 0) or when the battery is full (soc is 100). */ ret = regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_R1, bulk_reg, 3); if (ret < 0) return ret; charger->soc = get_unaligned_le24(bulk_reg); if (charger->soc > 10000) charger->soc = 10000; if (charger->soc < 0) charger->soc = 0; return 0; } static int rk817_read_or_set_full_charge_on_boot(struct rk817_charger *charger, struct power_supply_battery_info *bat_info) { struct rk808 *rk808 = charger->rk808; u8 bulk_reg[4]; u32 boot_voltage, boot_charge_mah; int ret, reg, off_time, tmp; bool first_boot; /* * Check if the battery is uninitalized. If it is, the columb counter * needs to be set up. */ ret = regmap_read(rk808->regmap, RK817_GAS_GAUGE_GG_STS, ®); if (ret < 0) return ret; first_boot = reg & RK817_BAT_CON; /* * If the battery is uninitialized, use the poweron voltage and an ocv * lookup to guess our charge. The number won't be very accurate until * we hit either our minimum voltage (0%) or full charge (100%). */ if (first_boot) { regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_PWRON_VOL_H, bulk_reg, 2); tmp = get_unaligned_be16(bulk_reg); boot_voltage = (charger->voltage_k * tmp) + 1000 * charger->voltage_b; /* * Since only implementation has no working thermistor, assume * 20C for OCV lookup. If lookup fails, report error with OCV * table. */ charger->soc = power_supply_batinfo_ocv2cap(bat_info, boot_voltage, 20) * 1000; if (charger->soc < 0) charger->soc = 0; /* Guess that full charge capacity is the design capacity */ charger->fcc_mah = charger->bat_charge_full_design_uah / 1000; /* * Set battery as "set up". BSP driver uses this value even * though datasheet claims it's a read-only value. */ regmap_write_bits(rk808->regmap, RK817_GAS_GAUGE_GG_STS, RK817_BAT_CON, 0); /* Save nvram values */ ret = rk817_record_battery_nvram_values(charger); if (ret < 0) return ret; } else { ret = rk817_read_battery_nvram_values(charger); if (ret < 0) return ret; regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3, bulk_reg, 4); tmp = get_unaligned_be32(bulk_reg); if (tmp < 0) tmp = 0; boot_charge_mah = ADC_TO_CHARGE_UAH(tmp, charger->res_div) / 1000; /* * Check if the columb counter has been off for more than 30 * minutes as it tends to drift downward. If so, re-init soc * with the boot voltage instead. Note the unit values for the * OFF_CNT register appear to be in decaminutes and stops * counting at 2550 (0xFF) minutes. BSP kernel used OCV, but * for me occasionally that would show invalid values. Boot * voltage is only accurate for me on first poweron (not * reboots), but we shouldn't ever encounter an OFF_CNT more * than 0 on a reboot anyway. */ regmap_read(rk808->regmap, RK817_GAS_GAUGE_OFF_CNT, &off_time); if (off_time >= 3) { regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_PWRON_VOL_H, bulk_reg, 2); tmp = get_unaligned_be16(bulk_reg); boot_voltage = (charger->voltage_k * tmp) + 1000 * charger->voltage_b; charger->soc = power_supply_batinfo_ocv2cap(bat_info, boot_voltage, 20) * 1000; } else { charger->soc = (boot_charge_mah * 1000 * 100 / charger->fcc_mah); } } /* * Now we have our full charge capacity and soc, init the columb * counter. */ boot_charge_mah = charger->soc * charger->fcc_mah / 100 / 1000; if (boot_charge_mah > charger->fcc_mah) boot_charge_mah = charger->fcc_mah; tmp = CHARGE_TO_ADC(boot_charge_mah, charger->res_div); put_unaligned_be32(tmp, bulk_reg); ret = regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_INIT_H3, bulk_reg, 4); if (ret < 0) return ret; /* Set QMAX value to max design capacity. */ tmp = CHARGE_TO_ADC((charger->bat_charge_full_design_uah / 1000), charger->res_div); put_unaligned_be32(tmp, bulk_reg); ret = regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_MAX_H3, bulk_reg, 4); if (ret < 0) return ret; return 0; } static int rk817_battery_init(struct rk817_charger *charger, struct power_supply_battery_info *bat_info) { struct rk808 *rk808 = charger->rk808; u32 tmp, max_chg_vol_mv, max_chg_cur_ma; u8 max_chg_vol_reg, chg_term_i_reg; int ret, chg_term_ma, max_chg_cur_reg; u8 bulk_reg[2]; /* Get initial plug state */ regmap_read(rk808->regmap, RK817_SYS_STS, &tmp); charger->plugged_in = (tmp & RK817_PLUG_IN_STS); /* * Turn on all ADC functions to measure battery, USB, and sys voltage, * as well as batt temp. Note only tested implementation so far does * not use a battery with a thermistor. */ regmap_write(rk808->regmap, RK817_GAS_GAUGE_ADC_CONFIG0, 0xfc); /* * Set relax mode voltage sampling interval and ADC offset calibration * interval to 8 minutes to mirror BSP kernel. Set voltage and current * modes to average to mirror BSP kernel. */ regmap_write(rk808->regmap, RK817_GAS_GAUGE_GG_CON, 0x04); /* Calibrate voltage like the BSP does here. */ rk817_bat_calib_vol(charger); /* Write relax threshold, derived from sleep enter current. */ tmp = CURRENT_TO_ADC(charger->sleep_enter_current_ua, charger->res_div); put_unaligned_be16(tmp, bulk_reg); regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_RELAX_THRE_H, bulk_reg, 2); /* Write sleep sample current, derived from sleep filter current. */ tmp = CURRENT_TO_ADC(charger->sleep_filter_current_ua, charger->res_div); put_unaligned_be16(tmp, bulk_reg); regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_SLEEP_CON_SAMP_CUR_H, bulk_reg, 2); /* Restart battery relax voltage */ regmap_write_bits(rk808->regmap, RK817_GAS_GAUGE_GG_STS, RK817_RELAX_VOL_UPD, (0x0 << 2)); /* * Set OCV Threshold Voltage to 127.5mV. This was hard coded like this * in the BSP. */ regmap_write(rk808->regmap, RK817_GAS_GAUGE_OCV_THRE_VOL, 0xff); /* * Set maximum charging voltage to battery max voltage. Trying to be * incredibly safe with these value, as setting them wrong could * overcharge the battery, which would be very bad. */ max_chg_vol_mv = bat_info->constant_charge_voltage_max_uv / 1000; max_chg_cur_ma = bat_info->constant_charge_current_max_ua / 1000; if (max_chg_vol_mv < 4100) { return dev_err_probe(charger->dev, -EINVAL, "invalid max charger voltage, value %u unsupported\n", max_chg_vol_mv * 1000); } if (max_chg_vol_mv > 4450) { dev_info(charger->dev, "Setting max charge voltage to 4450000uv\n"); max_chg_vol_mv = 4450; } if (max_chg_cur_ma < 500) { return dev_err_probe(charger->dev, -EINVAL, "invalid max charger current, value %u unsupported\n", max_chg_cur_ma * 1000); } if (max_chg_cur_ma > 3500) dev_info(charger->dev, "Setting max charge current to 3500000ua\n"); /* * Now that the values are sanity checked, if we subtract 4100 from the * max voltage and divide by 50, we conviently get the exact value for * the registers, which are 4.1v, 4.15v, 4.2v, 4.25v, 4.3v, 4.35v, * 4.4v, and 4.45v; these correspond to values 0x00 through 0x07. */ max_chg_vol_reg = (max_chg_vol_mv - 4100) / 50; max_chg_cur_reg = rk817_chg_cur_to_reg(max_chg_cur_ma); if (max_chg_vol_reg < 0 || max_chg_vol_reg > 7) { return dev_err_probe(charger->dev, -EINVAL, "invalid max charger voltage, value %u unsupported\n", max_chg_vol_mv * 1000); } if (max_chg_cur_reg < 0 || max_chg_cur_reg > 7) { return dev_err_probe(charger->dev, -EINVAL, "invalid max charger current, value %u unsupported\n", max_chg_cur_ma * 1000); } /* * Write the values to the registers, and deliver an emergency warning * in the event they are not written correctly. */ ret = regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_OUT, RK817_CHRG_VOL_SEL, (max_chg_vol_reg << 4)); if (ret) { dev_emerg(charger->dev, "Danger, unable to set max charger voltage: %u\n", ret); } ret = regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_OUT, RK817_CHRG_CUR_SEL, max_chg_cur_reg); if (ret) { dev_emerg(charger->dev, "Danger, unable to set max charger current: %u\n", ret); } /* Set charge finishing mode to analog */ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_TERM, RK817_CHRG_TERM_ANA_DIG, (0x0 << 2)); /* * Set charge finish current, warn if value not in range and keep * default. */ chg_term_ma = bat_info->charge_term_current_ua / 1000; if (chg_term_ma < 150 || chg_term_ma > 400) { dev_warn(charger->dev, "Invalid charge termination %u, keeping default\n", chg_term_ma * 1000); chg_term_ma = 200; } /* * Values of 150ma, 200ma, 300ma, and 400ma correspond to 00, 01, 10, * and 11. */ chg_term_i_reg = (chg_term_ma - 100) / 100; regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_TERM, RK817_CHRG_TERM_ANA_SEL, chg_term_i_reg); ret = rk817_read_or_set_full_charge_on_boot(charger, bat_info); if (ret < 0) return ret; /* * Set minimum USB input voltage to 4.5v and enable USB voltage input * limit. */ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_VLIM_SEL, (0x05 << 4)); regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_VLIM_EN, (0x01 << 7)); /* * Set average USB input current limit to 1.5A and enable USB current * input limit. */ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_ILIM_SEL, 0x03); regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_ILIM_EN, (0x01 << 3)); return 0; } static void rk817_charging_monitor(struct work_struct *work) { struct rk817_charger *charger; charger = container_of(work, struct rk817_charger, work.work); rk817_read_props(charger); /* Run every 8 seconds like the BSP driver did. */ queue_delayed_work(system_wq, &charger->work, msecs_to_jiffies(8000)); } static int rk817_charger_probe(struct platform_device *pdev) { struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent); struct rk817_charger *charger; struct device_node *node; struct power_supply_battery_info *bat_info; struct device *dev = &pdev->dev; struct power_supply_config pscfg = {}; int plugin_irq, plugout_irq; int of_value; int ret; node = of_get_child_by_name(dev->parent->of_node, "charger"); if (!node) return -ENODEV; charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL); if (!charger) { of_node_put(node); return -ENOMEM; } charger->rk808 = rk808; charger->dev = &pdev->dev; platform_set_drvdata(pdev, charger); rk817_bat_calib_vol(charger); pscfg.drv_data = charger; pscfg.of_node = node; /* * Get sample resistor value. Note only values of 10000 or 20000 * microohms are allowed. Schematic for my test implementation (an * Odroid Go Advance) shows a 10 milliohm resistor for reference. */ ret = of_property_read_u32(node, "rockchip,resistor-sense-micro-ohms", &of_value); if (ret < 0) { return dev_err_probe(dev, ret, "Error reading sample resistor value\n"); } /* * Store as a 1 or a 2, since all we really use the value for is as a * divisor in some calculations. */ charger->res_div = (of_value == 20000) ? 2 : 1; /* * Get sleep enter current value. Not sure what this value is for * other than to help calibrate the relax threshold. */ ret = of_property_read_u32(node, "rockchip,sleep-enter-current-microamp", &of_value); if (ret < 0) { return dev_err_probe(dev, ret, "Error reading sleep enter cur value\n"); } charger->sleep_enter_current_ua = of_value; /* Get sleep filter current value */ ret = of_property_read_u32(node, "rockchip,sleep-filter-current-microamp", &of_value); if (ret < 0) { return dev_err_probe(dev, ret, "Error reading sleep filter cur value\n"); } charger->sleep_filter_current_ua = of_value; charger->bat_ps = devm_power_supply_register(&pdev->dev, &rk817_bat_desc, &pscfg); if (IS_ERR(charger->bat_ps)) return dev_err_probe(dev, -EINVAL, "Battery failed to probe\n"); charger->chg_ps = devm_power_supply_register(&pdev->dev, &rk817_chg_desc, &pscfg); if (IS_ERR(charger->chg_ps)) return dev_err_probe(dev, -EINVAL, "Charger failed to probe\n"); ret = power_supply_get_battery_info(charger->bat_ps, &bat_info); if (ret) { return dev_err_probe(dev, ret, "Unable to get battery info\n"); } if ((bat_info->charge_full_design_uah <= 0) || (bat_info->voltage_min_design_uv <= 0) || (bat_info->voltage_max_design_uv <= 0) || (bat_info->constant_charge_voltage_max_uv <= 0) || (bat_info->constant_charge_current_max_ua <= 0) || (bat_info->charge_term_current_ua <= 0)) { return dev_err_probe(dev, -EINVAL, "Required bat info missing or invalid\n"); } charger->bat_charge_full_design_uah = bat_info->charge_full_design_uah; charger->bat_voltage_min_design_uv = bat_info->voltage_min_design_uv; charger->bat_voltage_max_design_uv = bat_info->voltage_max_design_uv; /* * Has to run after power_supply_get_battery_info as it depends on some * values discovered from that routine. */ ret = rk817_battery_init(charger, bat_info); if (ret) return ret; power_supply_put_battery_info(charger->bat_ps, bat_info); plugin_irq = platform_get_irq(pdev, 0); if (plugin_irq < 0) return plugin_irq; plugout_irq = platform_get_irq(pdev, 1); if (plugout_irq < 0) return plugout_irq; ret = devm_request_threaded_irq(charger->dev, plugin_irq, NULL, rk817_plug_in_isr, IRQF_TRIGGER_RISING | IRQF_ONESHOT, "rk817_plug_in", charger); if (ret) { return dev_err_probe(&pdev->dev, ret, "plug_in_irq request failed!\n"); } ret = devm_request_threaded_irq(charger->dev, plugout_irq, NULL, rk817_plug_out_isr, IRQF_TRIGGER_RISING | IRQF_ONESHOT, "rk817_plug_out", charger); if (ret) { return dev_err_probe(&pdev->dev, ret, "plug_out_irq request failed!\n"); } ret = devm_delayed_work_autocancel(&pdev->dev, &charger->work, rk817_charging_monitor); if (ret) return ret; /* Force the first update immediately. */ mod_delayed_work(system_wq, &charger->work, 0); return 0; } static struct platform_driver rk817_charger_driver = { .probe = rk817_charger_probe, .driver = { .name = "rk817-charger", }, }; module_platform_driver(rk817_charger_driver); MODULE_DESCRIPTION("Battery power supply driver for RK817 PMIC"); MODULE_AUTHOR("Maya Matuszczyk <maccraft123mc@gmail.com>"); MODULE_AUTHOR("Chris Morgan <macromorgan@hotmail.com>"); MODULE_LICENSE("GPL");