// SPDX-License-Identifier: GPL-2.0-only /* * max77759_charger.c - Battery charger driver for MAX77759 charger device. * * Copyright 2025 Google LLC. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* Default values for Fast Charge Current & Float Voltage */ #define CHG_CC_DEFAULT_UA 2266770 #define CHG_FV_DEFAULT_MV 4300 #define MAX_NUM_RETRIES 3 #define PSY_WORK_RETRY_DELAY_MS 10 #define FOREACH_IRQ(S) \ S(AICL), \ S(CHGIN), \ S(CHG), \ S(INLIM), \ S(BAT_OILO), \ S(CHG_STA_CC), \ S(CHG_STA_CV), \ S(CHG_STA_TO), \ S(CHG_STA_DONE) #define GENERATE_ENUM(e) e #define GENERATE_STRING(s) #s enum { FOREACH_IRQ(GENERATE_ENUM) }; static const char *const chgr_irqs_str[] = { FOREACH_IRQ(GENERATE_STRING) }; #define NUM_IRQS ARRAY_SIZE(chgr_irqs_str) /* Fast charge current limits (in uA) */ static const struct linear_range chgcc_limit_ranges[] = { LINEAR_RANGE(133330, 0x0, 0x2, 0), LINEAR_RANGE(200000, 0x3, 0x3C, 66670), }; /* Charge Termination Voltage Limits (in mV) */ static const struct linear_range chg_cv_prm_ranges[] = { LINEAR_RANGE(3800, 0x38, 0x39, 100), LINEAR_RANGE(4000, 0x0, 0x32, 10), }; /* USB input current limits (in uA) */ static const struct linear_range chgin_ilim_ranges[] = { LINEAR_RANGE(100000, 0x3, 0x7F, 25000), }; struct max77759_charger { struct device *dev; struct regmap *regmap; struct power_supply *psy; struct regulator_dev *chgin_otg_rdev; struct notifier_block nb; struct power_supply *tcpm_psy; struct delayed_work psy_work; struct mutex retry_lock; /* Protects psy_work_retry_cnt */ u32 psy_work_retry_cnt; int irqs[NUM_IRQS]; struct mutex lock; /* protects the state below */ enum max77759_chgr_mode mode; }; static inline int unlock_prot_regs(struct max77759_charger *chg, bool unlock) { return regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_06, MAX77759_CHGR_REG_CHG_CNFG_06_CHGPROT, unlock ? MAX77759_CHGR_REG_CHG_CNFG_06_CHGPROT : 0); } static int charger_input_valid(struct max77759_charger *chg) { u32 val; int ret; ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_INT_OK, &val); if (ret) return ret; return (val & MAX77759_CHGR_REG_CHG_INT_CHG) && (val & MAX77759_CHGR_REG_CHG_INT_CHGIN); } static int get_online(struct max77759_charger *chg) { u32 val; int ret; ret = charger_input_valid(chg); if (ret <= 0) return ret; ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_DETAILS_02, &val); if (ret) return ret; guard(mutex)(&chg->lock); return (val & MAX77759_CHGR_REG_CHG_DETAILS_02_CHGIN_STS) && (chg->mode == MAX77759_CHGR_MODE_CHG_BUCK_ON); } static int get_status(struct max77759_charger *chg) { u32 val; int ret; ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_DETAILS_01, &val); if (ret) return ret; switch (FIELD_GET(MAX77759_CHGR_REG_CHG_DETAILS_01_CHG_DTLS, val)) { case MAX77759_CHGR_CHG_DTLS_PREQUAL: case MAX77759_CHGR_CHG_DTLS_CC: case MAX77759_CHGR_CHG_DTLS_CV: case MAX77759_CHGR_CHG_DTLS_TO: return POWER_SUPPLY_STATUS_CHARGING; case MAX77759_CHGR_CHG_DTLS_DONE: return POWER_SUPPLY_STATUS_FULL; case MAX77759_CHGR_CHG_DTLS_TIMER_FAULT: case MAX77759_CHGR_CHG_DTLS_SUSP_BATT_THM: case MAX77759_CHGR_CHG_DTLS_OFF_WDOG_TIMER: case MAX77759_CHGR_CHG_DTLS_SUSP_JEITA: return POWER_SUPPLY_STATUS_NOT_CHARGING; case MAX77759_CHGR_CHG_DTLS_OFF: return POWER_SUPPLY_STATUS_DISCHARGING; default: break; } return POWER_SUPPLY_STATUS_UNKNOWN; } static int get_charge_type(struct max77759_charger *chg) { u32 val; int ret; ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_DETAILS_01, &val); if (ret) return ret; switch (FIELD_GET(MAX77759_CHGR_REG_CHG_DETAILS_01_CHG_DTLS, val)) { case MAX77759_CHGR_CHG_DTLS_PREQUAL: return POWER_SUPPLY_CHARGE_TYPE_TRICKLE; case MAX77759_CHGR_CHG_DTLS_CC: case MAX77759_CHGR_CHG_DTLS_CV: return POWER_SUPPLY_CHARGE_TYPE_FAST; case MAX77759_CHGR_CHG_DTLS_TO: return POWER_SUPPLY_CHARGE_TYPE_STANDARD; case MAX77759_CHGR_CHG_DTLS_DONE: case MAX77759_CHGR_CHG_DTLS_TIMER_FAULT: case MAX77759_CHGR_CHG_DTLS_SUSP_BATT_THM: case MAX77759_CHGR_CHG_DTLS_OFF_WDOG_TIMER: case MAX77759_CHGR_CHG_DTLS_SUSP_JEITA: case MAX77759_CHGR_CHG_DTLS_OFF: return POWER_SUPPLY_CHARGE_TYPE_NONE; default: break; } return POWER_SUPPLY_CHARGE_TYPE_UNKNOWN; } static int get_chg_health(struct max77759_charger *chg) { u32 val; int ret; ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_DETAILS_00, &val); if (ret) return ret; switch (FIELD_GET(MAX77759_CHGR_REG_CHG_DETAILS_00_CHGIN_DTLS, val)) { case MAX77759_CHGR_CHGIN_DTLS_VBUS_UNDERVOLTAGE: case MAX77759_CHGR_CHGIN_DTLS_VBUS_MARGINAL_VOLTAGE: return POWER_SUPPLY_HEALTH_UNDERVOLTAGE; case MAX77759_CHGR_CHGIN_DTLS_VBUS_OVERVOLTAGE: return POWER_SUPPLY_HEALTH_OVERVOLTAGE; case MAX77759_CHGR_CHGIN_DTLS_VBUS_VALID: return POWER_SUPPLY_HEALTH_GOOD; default: break; } return POWER_SUPPLY_HEALTH_UNKNOWN; } static int get_batt_health(struct max77759_charger *chg) { u32 val; int ret; ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_DETAILS_01, &val); if (ret) return ret; switch (FIELD_GET(MAX77759_CHGR_REG_CHG_DETAILS_01_BAT_DTLS, val)) { case MAX77759_CHGR_BAT_DTLS_NO_BATT_CHG_SUSP: return POWER_SUPPLY_HEALTH_NO_BATTERY; case MAX77759_CHGR_BAT_DTLS_DEAD_BATTERY: return POWER_SUPPLY_HEALTH_DEAD; case MAX77759_CHGR_BAT_DTLS_BAT_CHG_TIMER_FAULT: return POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE; case MAX77759_CHGR_BAT_DTLS_BAT_OKAY: case MAX77759_CHGR_BAT_DTLS_BAT_ONLY_MODE: return POWER_SUPPLY_HEALTH_GOOD; case MAX77759_CHGR_BAT_DTLS_BAT_UNDERVOLTAGE: return POWER_SUPPLY_HEALTH_UNDERVOLTAGE; case MAX77759_CHGR_BAT_DTLS_BAT_OVERVOLTAGE: return POWER_SUPPLY_HEALTH_OVERVOLTAGE; case MAX77759_CHGR_BAT_DTLS_BAT_OVERCURRENT: return POWER_SUPPLY_HEALTH_OVERCURRENT; default: break; } return POWER_SUPPLY_HEALTH_UNKNOWN; } static int get_health(struct max77759_charger *chg) { int ret; ret = get_online(chg); if (ret < 0) return ret; if (ret) { ret = get_chg_health(chg); if (ret < 0 || ret != POWER_SUPPLY_HEALTH_GOOD) return ret; } return get_batt_health(chg); } static int get_fast_charge_current(struct max77759_charger *chg) { u32 regval, val; int ret; ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_02, ®val); if (ret) return ret; regval = FIELD_GET(MAX77759_CHGR_REG_CHG_CNFG_02_CHGCC, regval); ret = linear_range_get_value_array(chgcc_limit_ranges, ARRAY_SIZE(chgcc_limit_ranges), regval, &val); return ret ? ret : val; } static int set_fast_charge_current_limit(struct max77759_charger *chg, u32 cc_max_ua) { bool found; u32 regval; linear_range_get_selector_high_array(chgcc_limit_ranges, ARRAY_SIZE(chgcc_limit_ranges), cc_max_ua, ®val, &found); if (!found) return -EINVAL; return regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_02, MAX77759_CHGR_REG_CHG_CNFG_02_CHGCC, regval); } static int get_float_voltage(struct max77759_charger *chg) { u32 regval, val; int ret; ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_04, ®val); if (ret) return ret; regval = FIELD_GET(MAX77759_CHGR_REG_CHG_CNFG_04_CHG_CV_PRM, regval); ret = linear_range_get_value_array(chg_cv_prm_ranges, ARRAY_SIZE(chg_cv_prm_ranges), regval, &val); return ret ? ret : val; } static int set_float_voltage_limit(struct max77759_charger *chg, u32 fv_mv) { u32 regval; bool found; linear_range_get_selector_high_array(chg_cv_prm_ranges, ARRAY_SIZE(chg_cv_prm_ranges), fv_mv, ®val, &found); if (!found) return -EINVAL; return regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_04, MAX77759_CHGR_REG_CHG_CNFG_04_CHG_CV_PRM, regval); } static int get_input_current_limit(struct max77759_charger *chg) { u32 regval, val; int ret; ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_09, ®val); if (ret) return ret; regval = FIELD_GET(MAX77759_CHGR_REG_CHG_CNFG_09_CHGIN_ILIM, regval); regval = umax(regval, chgin_ilim_ranges[0].min_sel); ret = linear_range_get_value_array(chgin_ilim_ranges, ARRAY_SIZE(chgin_ilim_ranges), regval, &val); return ret ? ret : val; } static int set_input_current_limit(struct max77759_charger *chg, int ilim_ua) { u32 regval; if (ilim_ua < 0) return -EINVAL; linear_range_get_selector_within(chgin_ilim_ranges, ilim_ua, ®val); return regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_09, MAX77759_CHGR_REG_CHG_CNFG_09_CHGIN_ILIM, regval); } static const enum power_supply_property max77759_charger_props[] = { POWER_SUPPLY_PROP_ONLINE, POWER_SUPPLY_PROP_PRESENT, POWER_SUPPLY_PROP_STATUS, POWER_SUPPLY_PROP_CHARGE_TYPE, POWER_SUPPLY_PROP_HEALTH, POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX, POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX, POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT, }; static int max77759_charger_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *pval) { struct max77759_charger *chg = power_supply_get_drvdata(psy); int ret; switch (psp) { case POWER_SUPPLY_PROP_ONLINE: ret = get_online(chg); break; case POWER_SUPPLY_PROP_PRESENT: ret = charger_input_valid(chg); break; case POWER_SUPPLY_PROP_STATUS: ret = get_status(chg); break; case POWER_SUPPLY_PROP_CHARGE_TYPE: ret = get_charge_type(chg); break; case POWER_SUPPLY_PROP_HEALTH: ret = get_health(chg); break; case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX: ret = get_fast_charge_current(chg); break; case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX: ret = get_float_voltage(chg); break; case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT: ret = get_input_current_limit(chg); break; default: ret = -EINVAL; } pval->intval = ret; return ret < 0 ? ret : 0; } static const struct power_supply_desc max77759_charger_desc = { .name = "max77759-charger", .type = POWER_SUPPLY_TYPE_USB, .properties = max77759_charger_props, .num_properties = ARRAY_SIZE(max77759_charger_props), .get_property = max77759_charger_get_property, }; static int charger_set_mode(struct max77759_charger *chg, enum max77759_chgr_mode mode) { int ret; guard(mutex)(&chg->lock); if (chg->mode == mode) return 0; if ((mode == MAX77759_CHGR_MODE_CHG_BUCK_ON || mode == MAX77759_CHGR_MODE_OTG_BOOST_ON) && chg->mode != MAX77759_CHGR_MODE_OFF) { dev_err(chg->dev, "Invalid mode transition from %d to %d\n", chg->mode, mode); return -EINVAL; } ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_00, MAX77759_CHGR_REG_CHG_CNFG_00_MODE, mode); if (ret) return ret; chg->mode = mode; return 0; } static int enable_chgin_otg(struct regulator_dev *rdev) { struct max77759_charger *chg = rdev_get_drvdata(rdev); return charger_set_mode(chg, MAX77759_CHGR_MODE_OTG_BOOST_ON); } static int disable_chgin_otg(struct regulator_dev *rdev) { struct max77759_charger *chg = rdev_get_drvdata(rdev); return charger_set_mode(chg, MAX77759_CHGR_MODE_OFF); } static int chgin_otg_status(struct regulator_dev *rdev) { struct max77759_charger *chg = rdev_get_drvdata(rdev); guard(mutex)(&chg->lock); return chg->mode == MAX77759_CHGR_MODE_OTG_BOOST_ON; } static const struct regulator_ops chgin_otg_reg_ops = { .enable = enable_chgin_otg, .disable = disable_chgin_otg, .is_enabled = chgin_otg_status, }; static const struct regulator_desc chgin_otg_reg_desc = { .name = "chgin-otg", .of_match = of_match_ptr("chgin-otg-regulator"), .owner = THIS_MODULE, .ops = &chgin_otg_reg_ops, .fixed_uV = 5000000, .n_voltages = 1, }; static irqreturn_t irq_handler(int irq, void *data) { struct max77759_charger *chg = data; power_supply_changed(chg->psy); return IRQ_HANDLED; } static irqreturn_t bat_oilo_irq_handler(int irq, void *data) { struct max77759_charger *chg = data; dev_warn_ratelimited(chg->dev, "Battery over-current threshold crossed\n"); return irq_handler(irq, data); } static int max77759_init_irqhandler(struct max77759_charger *chg) { struct device *dev = chg->dev; irq_handler_t thread_fn; char *name; int i, ret; for (i = 0; i < ARRAY_SIZE(chgr_irqs_str); i++) { ret = platform_get_irq_byname(to_platform_device(dev), chgr_irqs_str[i]); if (ret < 0) return dev_err_probe(dev, ret, "Failed to get irq resource for %s\n", chgr_irqs_str[i]); chg->irqs[i] = ret; name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s", dev_name(dev), chgr_irqs_str[i]); if (!name) return dev_err_probe(dev, -ENOMEM, "Failed to allocate space for irqname: %s\n", chgr_irqs_str[i]); if (i == BAT_OILO) thread_fn = bat_oilo_irq_handler; else thread_fn = irq_handler; ret = devm_request_threaded_irq(dev, chg->irqs[i], NULL, thread_fn, 0, name, chg); if (ret) return dev_err_probe(dev, ret, "Unable to register irq handler for %s\n", chgr_irqs_str[i]); } return 0; } static int max77759_charger_init(struct max77759_charger *chg) { struct power_supply_battery_info *info; u32 regval, fast_chg_curr, fv; int ret; ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_00, ®val); if (ret) return ret; chg->mode = FIELD_GET(MAX77759_CHGR_REG_CHG_CNFG_00_MODE, regval); ret = charger_set_mode(chg, MAX77759_CHGR_MODE_OFF); if (ret) return ret; if (power_supply_get_battery_info(chg->psy, &info)) { fv = CHG_FV_DEFAULT_MV; fast_chg_curr = CHG_CC_DEFAULT_UA; } else { fv = info->constant_charge_voltage_max_uv / 1000; fast_chg_curr = info->constant_charge_current_max_ua; } ret = set_fast_charge_current_limit(chg, fast_chg_curr); if (ret) return ret; ret = set_float_voltage_limit(chg, fv); if (ret) return ret; ret = unlock_prot_regs(chg, true); if (ret) return ret; /* Disable wireless charging input */ ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_12, MAX77759_CHGR_REG_CHG_CNFG_12_WCINSEL, 0); if (ret) goto relock; ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_18, MAX77759_CHGR_REG_CHG_CNFG_18_WDTEN, 0); if (ret) goto relock; return unlock_prot_regs(chg, false); relock: (void)unlock_prot_regs(chg, false); return ret; } static void psy_work_item(struct work_struct *work) { struct max77759_charger *chg = container_of(work, struct max77759_charger, psy_work.work); union power_supply_propval current_limit, online; int ret; ret = power_supply_get_property(chg->tcpm_psy, POWER_SUPPLY_PROP_CURRENT_MAX, ¤t_limit); if (ret) { dev_err(chg->dev, "Failed to get CURRENT_MAX psy property, ret=%d\n", ret); goto err; } ret = power_supply_get_property(chg->tcpm_psy, POWER_SUPPLY_PROP_ONLINE, &online); if (ret) { dev_err(chg->dev, "Failed to get ONLINE psy property, ret=%d\n", ret); goto err; } if (online.intval && current_limit.intval) { ret = set_input_current_limit(chg, current_limit.intval); if (ret) { dev_err(chg->dev, "Unable to set current limit, ret=%d\n", ret); goto err; } charger_set_mode(chg, MAX77759_CHGR_MODE_CHG_BUCK_ON); } else { charger_set_mode(chg, MAX77759_CHGR_MODE_OFF); } scoped_guard(mutex, &chg->retry_lock) { if (chg->psy_work_retry_cnt) dev_dbg(chg->dev, "chg psy_work succeeded after %u tries\n", chg->psy_work_retry_cnt); chg->psy_work_retry_cnt = 0; } return; err: charger_set_mode(chg, MAX77759_CHGR_MODE_OFF); scoped_guard(mutex, &chg->retry_lock) { if (chg->psy_work_retry_cnt >= MAX_NUM_RETRIES) { dev_err(chg->dev, "chg psy work failed, giving up\n"); return; } ++chg->psy_work_retry_cnt; dev_dbg(chg->dev, "Retrying %u/%u chg psy_work\n", chg->psy_work_retry_cnt, MAX_NUM_RETRIES); schedule_delayed_work(&chg->psy_work, msecs_to_jiffies(PSY_WORK_RETRY_DELAY_MS)); } } static int psy_changed(struct notifier_block *nb, unsigned long evt, void *data) { struct max77759_charger *chg = container_of(nb, struct max77759_charger, nb); static const char *psy_name = "tcpm-source"; struct power_supply *psy = data; if (!strnstr(psy->desc->name, psy_name, strlen(psy_name)) || evt != PSY_EVENT_PROP_CHANGED) return NOTIFY_OK; chg->tcpm_psy = psy; scoped_guard(mutex, &chg->retry_lock) chg->psy_work_retry_cnt = 0; schedule_delayed_work(&chg->psy_work, 0); return NOTIFY_OK; } static void max_tcpci_unregister_psy_notifier(void *nb) { power_supply_unreg_notifier(nb); } static int max77759_charger_probe(struct platform_device *pdev) { struct regulator_config chgin_otg_reg_cfg; struct power_supply_config psy_cfg; struct device *dev = &pdev->dev; struct max77759_charger *chg; int ret; device_set_of_node_from_dev(dev, dev->parent); chg = devm_kzalloc(dev, sizeof(*chg), GFP_KERNEL); if (!chg) return -ENOMEM; platform_set_drvdata(pdev, chg); chg->dev = dev; chg->regmap = dev_get_regmap(dev->parent, "charger"); if (!chg->regmap) return dev_err_probe(dev, -ENODEV, "Missing regmap\n"); ret = devm_mutex_init(dev, &chg->lock); if (ret) return dev_err_probe(dev, ret, "Failed to initialize lock\n"); ret = devm_mutex_init(dev, &chg->retry_lock); if (ret) return dev_err_probe(dev, ret, "Failed to initialize retry_lock\n"); psy_cfg.fwnode = dev_fwnode(dev); psy_cfg.drv_data = chg; chg->psy = devm_power_supply_register(dev, &max77759_charger_desc, &psy_cfg); if (IS_ERR(chg->psy)) return dev_err_probe(dev, PTR_ERR(chg->psy), "Failed to register psy\n"); ret = max77759_charger_init(chg); if (ret) return dev_err_probe(dev, ret, "Failed to initialize max77759 charger\n"); chgin_otg_reg_cfg.dev = dev; chgin_otg_reg_cfg.driver_data = chg; chgin_otg_reg_cfg.of_node = dev_of_node(dev); chg->chgin_otg_rdev = devm_regulator_register(dev, &chgin_otg_reg_desc, &chgin_otg_reg_cfg); if (IS_ERR(chg->chgin_otg_rdev)) return dev_err_probe(dev, PTR_ERR(chg->chgin_otg_rdev), "Failed to register chgin otg regulator\n"); ret = devm_delayed_work_autocancel(dev, &chg->psy_work, psy_work_item); if (ret) return dev_err_probe(dev, ret, "Failed to initialize psy work\n"); chg->nb.notifier_call = psy_changed; ret = power_supply_reg_notifier(&chg->nb); if (ret) return dev_err_probe(dev, ret, "Unable to register psy notifier\n"); ret = devm_add_action_or_reset(dev, max_tcpci_unregister_psy_notifier, &chg->nb); if (ret) return dev_err_probe(dev, ret, "Failed to add devm action to unregister psy notifier\n"); return max77759_init_irqhandler(chg); } static const struct platform_device_id max77759_charger_id[] = { { .name = "max77759-charger", }, { } }; MODULE_DEVICE_TABLE(platform, max77759_charger_id); static struct platform_driver max77759_charger_driver = { .driver = { .name = "max77759-charger", .probe_type = PROBE_PREFER_ASYNCHRONOUS, }, .probe = max77759_charger_probe, .id_table = max77759_charger_id, }; module_platform_driver(max77759_charger_driver); MODULE_AUTHOR("Amit Sunil Dhamne "); MODULE_DESCRIPTION("Maxim MAX77759 charger driver"); MODULE_LICENSE("GPL");