// SPDX-License-Identifier: GPL-2.0+ // // max77693_charger.c - Battery charger driver for the Maxim 77693 // // Copyright (C) 2014 Samsung Electronics // Krzysztof Kozlowski #include #include #include #include #include #include #include #define MAX77693_CHARGER_NAME "max77693-charger" static const char *max77693_charger_model = "MAX77693"; static const char *max77693_charger_manufacturer = "Maxim Integrated"; struct max77693_charger { struct device *dev; struct max77693_dev *max77693; struct power_supply *charger; u32 constant_volt; u32 min_system_volt; u32 thermal_regulation_temp; u32 batttery_overcurrent; u32 charge_input_threshold_volt; }; static int max77693_get_charger_state(struct regmap *regmap, int *val) { int ret; unsigned int data; ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data); if (ret < 0) return ret; data &= CHG_DETAILS_01_CHG_MASK; data >>= CHG_DETAILS_01_CHG_SHIFT; switch (data) { case MAX77693_CHARGING_PREQUALIFICATION: case MAX77693_CHARGING_FAST_CONST_CURRENT: case MAX77693_CHARGING_FAST_CONST_VOLTAGE: case MAX77693_CHARGING_TOP_OFF: /* In high temp the charging current is reduced, but still charging */ case MAX77693_CHARGING_HIGH_TEMP: *val = POWER_SUPPLY_STATUS_CHARGING; break; case MAX77693_CHARGING_DONE: *val = POWER_SUPPLY_STATUS_FULL; break; case MAX77693_CHARGING_TIMER_EXPIRED: case MAX77693_CHARGING_THERMISTOR_SUSPEND: *val = POWER_SUPPLY_STATUS_NOT_CHARGING; break; case MAX77693_CHARGING_OFF: case MAX77693_CHARGING_OVER_TEMP: case MAX77693_CHARGING_WATCHDOG_EXPIRED: *val = POWER_SUPPLY_STATUS_DISCHARGING; break; case MAX77693_CHARGING_RESERVED: default: *val = POWER_SUPPLY_STATUS_UNKNOWN; } return 0; } static int max77693_get_charge_type(struct regmap *regmap, int *val) { int ret; unsigned int data; ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data); if (ret < 0) return ret; data &= CHG_DETAILS_01_CHG_MASK; data >>= CHG_DETAILS_01_CHG_SHIFT; switch (data) { case MAX77693_CHARGING_PREQUALIFICATION: /* * Top-off: trickle or fast? In top-off the current varies between * 100 and 250 mA. It is higher than prequalification current. */ case MAX77693_CHARGING_TOP_OFF: *val = POWER_SUPPLY_CHARGE_TYPE_TRICKLE; break; case MAX77693_CHARGING_FAST_CONST_CURRENT: case MAX77693_CHARGING_FAST_CONST_VOLTAGE: /* In high temp the charging current is reduced, but still charging */ case MAX77693_CHARGING_HIGH_TEMP: *val = POWER_SUPPLY_CHARGE_TYPE_FAST; break; case MAX77693_CHARGING_DONE: case MAX77693_CHARGING_TIMER_EXPIRED: case MAX77693_CHARGING_THERMISTOR_SUSPEND: case MAX77693_CHARGING_OFF: case MAX77693_CHARGING_OVER_TEMP: case MAX77693_CHARGING_WATCHDOG_EXPIRED: *val = POWER_SUPPLY_CHARGE_TYPE_NONE; break; case MAX77693_CHARGING_RESERVED: default: *val = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN; } return 0; } /* * Supported health statuses: * - POWER_SUPPLY_HEALTH_DEAD * - POWER_SUPPLY_HEALTH_GOOD * - POWER_SUPPLY_HEALTH_OVERVOLTAGE * - POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE * - POWER_SUPPLY_HEALTH_UNKNOWN * - POWER_SUPPLY_HEALTH_UNSPEC_FAILURE */ static int max77693_get_battery_health(struct regmap *regmap, int *val) { int ret; unsigned int data; ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data); if (ret < 0) return ret; data &= CHG_DETAILS_01_BAT_MASK; data >>= CHG_DETAILS_01_BAT_SHIFT; switch (data) { case MAX77693_BATTERY_NOBAT: *val = POWER_SUPPLY_HEALTH_DEAD; break; case MAX77693_BATTERY_PREQUALIFICATION: case MAX77693_BATTERY_GOOD: case MAX77693_BATTERY_LOWVOLTAGE: *val = POWER_SUPPLY_HEALTH_GOOD; break; case MAX77693_BATTERY_TIMER_EXPIRED: /* * Took longer to charge than expected, charging suspended. * Damaged battery? */ *val = POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE; break; case MAX77693_BATTERY_OVERVOLTAGE: *val = POWER_SUPPLY_HEALTH_OVERVOLTAGE; break; case MAX77693_BATTERY_OVERCURRENT: *val = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE; break; case MAX77693_BATTERY_RESERVED: default: *val = POWER_SUPPLY_HEALTH_UNKNOWN; break; } return 0; } static int max77693_get_present(struct regmap *regmap, int *val) { unsigned int data; int ret; /* * Read CHG_INT_OK register. High DETBAT bit here should be * equal to value 0x0 in CHG_DETAILS_01/BAT field. */ ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_INT_OK, &data); if (ret < 0) return ret; *val = (data & CHG_INT_OK_DETBAT_MASK) ? 0 : 1; return 0; } static int max77693_get_online(struct regmap *regmap, int *val) { unsigned int data; int ret; ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_INT_OK, &data); if (ret < 0) return ret; *val = (data & CHG_INT_OK_CHGIN_MASK) ? 1 : 0; return 0; } /* * There are *two* current limit registers: * - CHGIN limit, which limits the input current from the external charger; * - Fast charge current limit, which limits the current going to the battery. */ static int max77693_get_input_current_limit(struct regmap *regmap, int *val) { unsigned int data; int ret; ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_CNFG_09, &data); if (ret < 0) return ret; data &= CHG_CNFG_09_CHGIN_ILIM_MASK; data >>= CHG_CNFG_09_CHGIN_ILIM_SHIFT; if (data <= 0x03) /* The first four values (0x00..0x03) are 60mA */ *val = 60000; else *val = data * 20000; /* 20mA steps */ return 0; } static int max77693_get_fast_charge_current(struct regmap *regmap, int *val) { unsigned int data; int ret; ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_CNFG_02, &data); if (ret < 0) return ret; data &= CHG_CNFG_02_CC_MASK; data >>= CHG_CNFG_02_CC_SHIFT; *val = data * 33300; /* 33.3mA steps */ return 0; } static enum power_supply_property max77693_charger_props[] = { POWER_SUPPLY_PROP_STATUS, POWER_SUPPLY_PROP_CHARGE_TYPE, POWER_SUPPLY_PROP_HEALTH, POWER_SUPPLY_PROP_PRESENT, POWER_SUPPLY_PROP_ONLINE, POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT, POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX, POWER_SUPPLY_PROP_MODEL_NAME, POWER_SUPPLY_PROP_MANUFACTURER, }; static int max77693_charger_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) { struct max77693_charger *chg = power_supply_get_drvdata(psy); struct regmap *regmap = chg->max77693->regmap; int ret = 0; switch (psp) { case POWER_SUPPLY_PROP_STATUS: ret = max77693_get_charger_state(regmap, &val->intval); break; case POWER_SUPPLY_PROP_CHARGE_TYPE: ret = max77693_get_charge_type(regmap, &val->intval); break; case POWER_SUPPLY_PROP_HEALTH: ret = max77693_get_battery_health(regmap, &val->intval); break; case POWER_SUPPLY_PROP_PRESENT: ret = max77693_get_present(regmap, &val->intval); break; case POWER_SUPPLY_PROP_ONLINE: ret = max77693_get_online(regmap, &val->intval); break; case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT: ret = max77693_get_input_current_limit(regmap, &val->intval); break; case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX: ret = max77693_get_fast_charge_current(regmap, &val->intval); break; case POWER_SUPPLY_PROP_MODEL_NAME: val->strval = max77693_charger_model; break; case POWER_SUPPLY_PROP_MANUFACTURER: val->strval = max77693_charger_manufacturer; break; default: return -EINVAL; } return ret; } static const struct power_supply_desc max77693_charger_desc = { .name = MAX77693_CHARGER_NAME, .type = POWER_SUPPLY_TYPE_BATTERY, .properties = max77693_charger_props, .num_properties = ARRAY_SIZE(max77693_charger_props), .get_property = max77693_charger_get_property, }; static ssize_t device_attr_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count, int (*fn)(struct max77693_charger *, unsigned long)) { struct max77693_charger *chg = dev_get_drvdata(dev); unsigned long val; int ret; ret = kstrtoul(buf, 10, &val); if (ret) return ret; ret = fn(chg, val); if (ret) return ret; return count; } static ssize_t fast_charge_timer_show(struct device *dev, struct device_attribute *attr, char *buf) { struct max77693_charger *chg = dev_get_drvdata(dev); unsigned int data, val; int ret; ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_01, &data); if (ret < 0) return ret; data &= CHG_CNFG_01_FCHGTIME_MASK; data >>= CHG_CNFG_01_FCHGTIME_SHIFT; switch (data) { case 0x1 ... 0x7: /* Starting from 4 hours, step by 2 hours */ val = 4 + (data - 1) * 2; break; case 0x0: default: val = 0; break; } return sysfs_emit(buf, "%u\n", val); } static int max77693_set_fast_charge_timer(struct max77693_charger *chg, unsigned long hours) { unsigned int data; /* * 0x00 - disable * 0x01 - 4h * 0x02 - 6h * ... * 0x07 - 16h * Round down odd values. */ switch (hours) { case 4 ... 16: data = (hours - 4) / 2 + 1; break; case 0: /* Disable */ data = 0; break; default: return -EINVAL; } data <<= CHG_CNFG_01_FCHGTIME_SHIFT; return regmap_update_bits(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_01, CHG_CNFG_01_FCHGTIME_MASK, data); } static ssize_t fast_charge_timer_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { return device_attr_store(dev, attr, buf, count, max77693_set_fast_charge_timer); } static ssize_t top_off_threshold_current_show(struct device *dev, struct device_attribute *attr, char *buf) { struct max77693_charger *chg = dev_get_drvdata(dev); unsigned int data, val; int ret; ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_03, &data); if (ret < 0) return ret; data &= CHG_CNFG_03_TOITH_MASK; data >>= CHG_CNFG_03_TOITH_SHIFT; if (data <= 0x04) val = 100000 + data * 25000; else val = data * 50000; return sysfs_emit(buf, "%u\n", val); } static int max77693_set_top_off_threshold_current(struct max77693_charger *chg, unsigned long uamp) { unsigned int data; if (uamp < 100000 || uamp > 350000) return -EINVAL; if (uamp <= 200000) data = (uamp - 100000) / 25000; else /* (200000, 350000> */ data = uamp / 50000; data <<= CHG_CNFG_03_TOITH_SHIFT; return regmap_update_bits(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_03, CHG_CNFG_03_TOITH_MASK, data); } static ssize_t top_off_threshold_current_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { return device_attr_store(dev, attr, buf, count, max77693_set_top_off_threshold_current); } static ssize_t top_off_timer_show(struct device *dev, struct device_attribute *attr, char *buf) { struct max77693_charger *chg = dev_get_drvdata(dev); unsigned int data, val; int ret; ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_03, &data); if (ret < 0) return ret; data &= CHG_CNFG_03_TOTIME_MASK; data >>= CHG_CNFG_03_TOTIME_SHIFT; val = data * 10; return sysfs_emit(buf, "%u\n", val); } static int max77693_set_top_off_timer(struct max77693_charger *chg, unsigned long minutes) { unsigned int data; if (minutes > 70) return -EINVAL; data = minutes / 10; data <<= CHG_CNFG_03_TOTIME_SHIFT; return regmap_update_bits(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_03, CHG_CNFG_03_TOTIME_MASK, data); } static ssize_t top_off_timer_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { return device_attr_store(dev, attr, buf, count, max77693_set_top_off_timer); } static DEVICE_ATTR_RW(fast_charge_timer); static DEVICE_ATTR_RW(top_off_threshold_current); static DEVICE_ATTR_RW(top_off_timer); static int max77693_set_constant_volt(struct max77693_charger *chg, unsigned int uvolt) { unsigned int data; /* * 0x00 - 3.650 V * 0x01 - 3.675 V * ... * 0x1b - 4.325 V * 0x1c - 4.340 V * 0x1d - 4.350 V * 0x1e - 4.375 V * 0x1f - 4.400 V */ if (uvolt >= 3650000 && uvolt < 4340000) data = (uvolt - 3650000) / 25000; else if (uvolt >= 4340000 && uvolt < 4350000) data = 0x1c; else if (uvolt >= 4350000 && uvolt <= 4400000) data = 0x1d + (uvolt - 4350000) / 25000; else { dev_err(chg->dev, "Wrong value for charging constant voltage\n"); return -EINVAL; } data <<= CHG_CNFG_04_CHGCVPRM_SHIFT; dev_dbg(chg->dev, "Charging constant voltage: %u (0x%x)\n", uvolt, data); return regmap_update_bits(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_04, CHG_CNFG_04_CHGCVPRM_MASK, data); } static int max77693_set_min_system_volt(struct max77693_charger *chg, unsigned int uvolt) { unsigned int data; if (uvolt < 3000000 || uvolt > 3700000) { dev_err(chg->dev, "Wrong value for minimum system regulation voltage\n"); return -EINVAL; } data = (uvolt - 3000000) / 100000; data <<= CHG_CNFG_04_MINVSYS_SHIFT; dev_dbg(chg->dev, "Minimum system regulation voltage: %u (0x%x)\n", uvolt, data); return regmap_update_bits(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_04, CHG_CNFG_04_MINVSYS_MASK, data); } static int max77693_set_thermal_regulation_temp(struct max77693_charger *chg, unsigned int cels) { unsigned int data; switch (cels) { case 70: case 85: case 100: case 115: data = (cels - 70) / 15; break; default: dev_err(chg->dev, "Wrong value for thermal regulation loop temperature\n"); return -EINVAL; } data <<= CHG_CNFG_07_REGTEMP_SHIFT; dev_dbg(chg->dev, "Thermal regulation loop temperature: %u (0x%x)\n", cels, data); return regmap_update_bits(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_07, CHG_CNFG_07_REGTEMP_MASK, data); } static int max77693_set_batttery_overcurrent(struct max77693_charger *chg, unsigned int uamp) { unsigned int data; if (uamp && (uamp < 2000000 || uamp > 3500000)) { dev_err(chg->dev, "Wrong value for battery overcurrent\n"); return -EINVAL; } if (uamp) data = ((uamp - 2000000) / 250000) + 1; else data = 0; /* disable */ data <<= CHG_CNFG_12_B2SOVRC_SHIFT; dev_dbg(chg->dev, "Battery overcurrent: %u (0x%x)\n", uamp, data); return regmap_update_bits(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_12, CHG_CNFG_12_B2SOVRC_MASK, data); } static int max77693_set_charge_input_threshold_volt(struct max77693_charger *chg, unsigned int uvolt) { unsigned int data; switch (uvolt) { case 4300000: data = 0x0; break; case 4700000: case 4800000: case 4900000: data = (uvolt - 4700000) / 100000; break; default: dev_err(chg->dev, "Wrong value for charge input voltage regulation threshold\n"); return -EINVAL; } data <<= CHG_CNFG_12_VCHGINREG_SHIFT; dev_dbg(chg->dev, "Charge input voltage regulation threshold: %u (0x%x)\n", uvolt, data); return regmap_update_bits(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_12, CHG_CNFG_12_VCHGINREG_MASK, data); } /* * Sets charger registers to proper and safe default values. */ static int max77693_reg_init(struct max77693_charger *chg) { int ret; unsigned int data; /* Unlock charger register protection */ data = (0x3 << CHG_CNFG_06_CHGPROT_SHIFT); ret = regmap_update_bits(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_06, CHG_CNFG_06_CHGPROT_MASK, data); if (ret) { dev_err(chg->dev, "Error unlocking registers: %d\n", ret); return ret; } ret = max77693_set_fast_charge_timer(chg, DEFAULT_FAST_CHARGE_TIMER); if (ret) return ret; ret = max77693_set_top_off_threshold_current(chg, DEFAULT_TOP_OFF_THRESHOLD_CURRENT); if (ret) return ret; ret = max77693_set_top_off_timer(chg, DEFAULT_TOP_OFF_TIMER); if (ret) return ret; ret = max77693_set_constant_volt(chg, chg->constant_volt); if (ret) return ret; ret = max77693_set_min_system_volt(chg, chg->min_system_volt); if (ret) return ret; ret = max77693_set_thermal_regulation_temp(chg, chg->thermal_regulation_temp); if (ret) return ret; ret = max77693_set_batttery_overcurrent(chg, chg->batttery_overcurrent); if (ret) return ret; return max77693_set_charge_input_threshold_volt(chg, chg->charge_input_threshold_volt); } #ifdef CONFIG_OF static int max77693_dt_init(struct device *dev, struct max77693_charger *chg) { struct device_node *np = dev->of_node; if (!np) { dev_err(dev, "no charger OF node\n"); return -EINVAL; } if (of_property_read_u32(np, "maxim,constant-microvolt", &chg->constant_volt)) chg->constant_volt = DEFAULT_CONSTANT_VOLT; if (of_property_read_u32(np, "maxim,min-system-microvolt", &chg->min_system_volt)) chg->min_system_volt = DEFAULT_MIN_SYSTEM_VOLT; if (of_property_read_u32(np, "maxim,thermal-regulation-celsius", &chg->thermal_regulation_temp)) chg->thermal_regulation_temp = DEFAULT_THERMAL_REGULATION_TEMP; if (of_property_read_u32(np, "maxim,battery-overcurrent-microamp", &chg->batttery_overcurrent)) chg->batttery_overcurrent = DEFAULT_BATTERY_OVERCURRENT; if (of_property_read_u32(np, "maxim,charge-input-threshold-microvolt", &chg->charge_input_threshold_volt)) chg->charge_input_threshold_volt = DEFAULT_CHARGER_INPUT_THRESHOLD_VOLT; return 0; } #else /* CONFIG_OF */ static int max77693_dt_init(struct device *dev, struct max77693_charger *chg) { return 0; } #endif /* CONFIG_OF */ static int max77693_charger_probe(struct platform_device *pdev) { struct max77693_charger *chg; struct power_supply_config psy_cfg = {}; struct max77693_dev *max77693 = dev_get_drvdata(pdev->dev.parent); int ret; chg = devm_kzalloc(&pdev->dev, sizeof(*chg), GFP_KERNEL); if (!chg) return -ENOMEM; platform_set_drvdata(pdev, chg); chg->dev = &pdev->dev; chg->max77693 = max77693; ret = max77693_dt_init(&pdev->dev, chg); if (ret) return ret; ret = max77693_reg_init(chg); if (ret) return ret; psy_cfg.drv_data = chg; ret = device_create_file(&pdev->dev, &dev_attr_fast_charge_timer); if (ret) { dev_err(&pdev->dev, "failed: create fast charge timer sysfs entry\n"); goto err; } ret = device_create_file(&pdev->dev, &dev_attr_top_off_threshold_current); if (ret) { dev_err(&pdev->dev, "failed: create top off current sysfs entry\n"); goto err; } ret = device_create_file(&pdev->dev, &dev_attr_top_off_timer); if (ret) { dev_err(&pdev->dev, "failed: create top off timer sysfs entry\n"); goto err; } chg->charger = devm_power_supply_register(&pdev->dev, &max77693_charger_desc, &psy_cfg); if (IS_ERR(chg->charger)) { dev_err(&pdev->dev, "failed: power supply register\n"); ret = PTR_ERR(chg->charger); goto err; } return 0; err: device_remove_file(&pdev->dev, &dev_attr_top_off_timer); device_remove_file(&pdev->dev, &dev_attr_top_off_threshold_current); device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer); return ret; } static void max77693_charger_remove(struct platform_device *pdev) { device_remove_file(&pdev->dev, &dev_attr_top_off_timer); device_remove_file(&pdev->dev, &dev_attr_top_off_threshold_current); device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer); } static const struct platform_device_id max77693_charger_id[] = { { "max77693-charger", 0, }, { } }; MODULE_DEVICE_TABLE(platform, max77693_charger_id); static struct platform_driver max77693_charger_driver = { .driver = { .name = "max77693-charger", }, .probe = max77693_charger_probe, .remove = max77693_charger_remove, .id_table = max77693_charger_id, }; module_platform_driver(max77693_charger_driver); MODULE_AUTHOR("Krzysztof Kozlowski "); MODULE_DESCRIPTION("Maxim 77693 charger driver"); MODULE_LICENSE("GPL");