/* * max14577_charger.c - Battery charger driver for the Maxim 14577/77836 * * Copyright (C) 2013,2014 Samsung Electronics * Krzysztof Kozlowski <k.kozlowski@samsung.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include <linux/module.h> #include <linux/platform_device.h> #include <linux/power_supply.h> #include <linux/mfd/max14577-private.h> #include <linux/mfd/max14577.h> struct max14577_charger { struct device *dev; struct max14577 *max14577; struct power_supply *charger; struct max14577_charger_platform_data *pdata; }; /* * Helper function for mapping values of STATUS2/CHGTYP register on max14577 * and max77836 chipsets to enum maxim_muic_charger_type. */ static enum max14577_muic_charger_type maxim_get_charger_type( enum maxim_device_type dev_type, u8 val) { switch (val) { case MAX14577_CHARGER_TYPE_NONE: case MAX14577_CHARGER_TYPE_USB: case MAX14577_CHARGER_TYPE_DOWNSTREAM_PORT: case MAX14577_CHARGER_TYPE_DEDICATED_CHG: case MAX14577_CHARGER_TYPE_SPECIAL_500MA: case MAX14577_CHARGER_TYPE_SPECIAL_1A: return val; case MAX14577_CHARGER_TYPE_DEAD_BATTERY: case MAX14577_CHARGER_TYPE_RESERVED: if (dev_type == MAXIM_DEVICE_TYPE_MAX77836) val |= 0x8; return val; default: WARN_ONCE(1, "max14577: Unsupported chgtyp register value 0x%02x", val); return val; } } static int max14577_get_charger_state(struct max14577_charger *chg, int *val) { struct regmap *rmap = chg->max14577->regmap; int ret; u8 reg_data; /* * Charging occurs only if: * - CHGCTRL2/MBCHOSTEN == 1 * - STATUS2/CGMBC == 1 * * TODO: * - handle FULL after Top-off timer (EOC register may be off * and the charger won't be charging although MBCHOSTEN is on) * - handle properly dead-battery charging (respect timer) * - handle timers (fast-charge and prequal) /MBCCHGERR/ */ ret = max14577_read_reg(rmap, MAX14577_CHG_REG_CHG_CTRL2, ®_data); if (ret < 0) goto out; if ((reg_data & CHGCTRL2_MBCHOSTEN_MASK) == 0) { *val = POWER_SUPPLY_STATUS_DISCHARGING; goto out; } ret = max14577_read_reg(rmap, MAX14577_CHG_REG_STATUS3, ®_data); if (ret < 0) goto out; if (reg_data & STATUS3_CGMBC_MASK) { /* Charger or USB-cable is connected */ if (reg_data & STATUS3_EOC_MASK) *val = POWER_SUPPLY_STATUS_FULL; else *val = POWER_SUPPLY_STATUS_CHARGING; goto out; } *val = POWER_SUPPLY_STATUS_DISCHARGING; out: return ret; } /* * Supported charge types: * - POWER_SUPPLY_CHARGE_TYPE_NONE * - POWER_SUPPLY_CHARGE_TYPE_FAST */ static int max14577_get_charge_type(struct max14577_charger *chg, int *val) { int ret, charging; /* * TODO: CHARGE_TYPE_TRICKLE (VCHGR_RC or EOC)? * As spec says: * [after reaching EOC interrupt] * "When the battery is fully charged, the 30-minute (typ) * top-off timer starts. The device continues to trickle * charge the battery until the top-off timer runs out." */ ret = max14577_get_charger_state(chg, &charging); if (ret < 0) return ret; if (charging == POWER_SUPPLY_STATUS_CHARGING) *val = POWER_SUPPLY_CHARGE_TYPE_FAST; else *val = POWER_SUPPLY_CHARGE_TYPE_NONE; return 0; } static int max14577_get_online(struct max14577_charger *chg, int *val) { struct regmap *rmap = chg->max14577->regmap; u8 reg_data; int ret; enum max14577_muic_charger_type chg_type; ret = max14577_read_reg(rmap, MAX14577_MUIC_REG_STATUS2, ®_data); if (ret < 0) return ret; reg_data = ((reg_data & STATUS2_CHGTYP_MASK) >> STATUS2_CHGTYP_SHIFT); chg_type = maxim_get_charger_type(chg->max14577->dev_type, reg_data); switch (chg_type) { case MAX14577_CHARGER_TYPE_USB: case MAX14577_CHARGER_TYPE_DEDICATED_CHG: case MAX14577_CHARGER_TYPE_SPECIAL_500MA: case MAX14577_CHARGER_TYPE_SPECIAL_1A: case MAX14577_CHARGER_TYPE_DEAD_BATTERY: case MAX77836_CHARGER_TYPE_SPECIAL_BIAS: *val = 1; break; case MAX14577_CHARGER_TYPE_NONE: case MAX14577_CHARGER_TYPE_DOWNSTREAM_PORT: case MAX14577_CHARGER_TYPE_RESERVED: case MAX77836_CHARGER_TYPE_RESERVED: default: *val = 0; } return 0; } /* * Supported health statuses: * - POWER_SUPPLY_HEALTH_DEAD * - POWER_SUPPLY_HEALTH_OVERVOLTAGE * - POWER_SUPPLY_HEALTH_GOOD */ static int max14577_get_battery_health(struct max14577_charger *chg, int *val) { struct regmap *rmap = chg->max14577->regmap; int ret; u8 reg_data; enum max14577_muic_charger_type chg_type; ret = max14577_read_reg(rmap, MAX14577_MUIC_REG_STATUS2, ®_data); if (ret < 0) goto out; reg_data = ((reg_data & STATUS2_CHGTYP_MASK) >> STATUS2_CHGTYP_SHIFT); chg_type = maxim_get_charger_type(chg->max14577->dev_type, reg_data); if (chg_type == MAX14577_CHARGER_TYPE_DEAD_BATTERY) { *val = POWER_SUPPLY_HEALTH_DEAD; goto out; } ret = max14577_read_reg(rmap, MAX14577_CHG_REG_STATUS3, ®_data); if (ret < 0) goto out; if (reg_data & STATUS3_OVP_MASK) { *val = POWER_SUPPLY_HEALTH_OVERVOLTAGE; goto out; } /* Not dead, not overvoltage */ *val = POWER_SUPPLY_HEALTH_GOOD; out: return ret; } /* * Always returns 1. * The max14577 chip doesn't report any status of battery presence. * Lets assume that it will always be used with some battery. */ static int max14577_get_present(struct max14577_charger *chg, int *val) { *val = 1; return 0; } static int max14577_set_fast_charge_timer(struct max14577_charger *chg, unsigned long hours) { u8 reg_data; switch (hours) { case 5 ... 7: reg_data = hours - 3; break; case 0: /* Disable */ reg_data = 0x7; break; default: dev_err(chg->dev, "Wrong value for Fast-Charge Timer: %lu\n", hours); return -EINVAL; } reg_data <<= CHGCTRL1_TCHW_SHIFT; return max14577_update_reg(chg->max14577->regmap, MAX14577_REG_CHGCTRL1, CHGCTRL1_TCHW_MASK, reg_data); } static int max14577_init_constant_voltage(struct max14577_charger *chg, unsigned int uvolt) { u8 reg_data; if (uvolt < MAXIM_CHARGER_CONSTANT_VOLTAGE_MIN || uvolt > MAXIM_CHARGER_CONSTANT_VOLTAGE_MAX) return -EINVAL; if (uvolt == 4200000) reg_data = 0x0; else if (uvolt == MAXIM_CHARGER_CONSTANT_VOLTAGE_MAX) reg_data = 0x1f; else if (uvolt <= 4280000) { unsigned int val = uvolt; val -= MAXIM_CHARGER_CONSTANT_VOLTAGE_MIN; val /= MAXIM_CHARGER_CONSTANT_VOLTAGE_STEP; if (uvolt <= 4180000) reg_data = 0x1 + val; else reg_data = val; /* Fix for gap between 4.18V and 4.22V */ } else return -EINVAL; reg_data <<= CHGCTRL3_MBCCVWRC_SHIFT; return max14577_write_reg(chg->max14577->regmap, MAX14577_CHG_REG_CHG_CTRL3, reg_data); } static int max14577_init_eoc(struct max14577_charger *chg, unsigned int uamp) { unsigned int current_bits = 0xf; u8 reg_data; switch (chg->max14577->dev_type) { case MAXIM_DEVICE_TYPE_MAX77836: if (uamp < 5000) return -EINVAL; /* Requested current is too low */ if (uamp >= 7500 && uamp < 10000) current_bits = 0x0; else if (uamp <= 50000) { /* <5000, 7499> and <10000, 50000> */ current_bits = uamp / 5000; } else { uamp = min(uamp, 100000U) - 50000U; current_bits = 0xa + uamp / 10000; } break; case MAXIM_DEVICE_TYPE_MAX14577: default: if (uamp < MAX14577_CHARGER_EOC_CURRENT_LIMIT_MIN) return -EINVAL; /* Requested current is too low */ uamp = min(uamp, MAX14577_CHARGER_EOC_CURRENT_LIMIT_MAX); uamp -= MAX14577_CHARGER_EOC_CURRENT_LIMIT_MIN; current_bits = uamp / MAX14577_CHARGER_EOC_CURRENT_LIMIT_STEP; break; } reg_data = current_bits << CHGCTRL5_EOCS_SHIFT; return max14577_update_reg(chg->max14577->regmap, MAX14577_CHG_REG_CHG_CTRL5, CHGCTRL5_EOCS_MASK, reg_data); } static int max14577_init_fast_charge(struct max14577_charger *chg, unsigned int uamp) { u8 reg_data; int ret; const struct maxim_charger_current *limits = &maxim_charger_currents[chg->max14577->dev_type]; ret = maxim_charger_calc_reg_current(limits, uamp, uamp, ®_data); if (ret) { dev_err(chg->dev, "Wrong value for fast charge: %u\n", uamp); return ret; } return max14577_update_reg(chg->max14577->regmap, MAX14577_CHG_REG_CHG_CTRL4, CHGCTRL4_MBCICHWRCL_MASK | CHGCTRL4_MBCICHWRCH_MASK, reg_data); } /* * Sets charger registers to proper and safe default values. * Some of these values are equal to defaults in MAX14577E * data sheet but there are minor differences. */ static int max14577_charger_reg_init(struct max14577_charger *chg) { struct regmap *rmap = chg->max14577->regmap; u8 reg_data; int ret; /* * Charger-Type Manual Detection, default off (set CHGTYPMAN to 0) * Charger-Detection Enable, default on (set CHGDETEN to 1) * Combined mask of CHGDETEN and CHGTYPMAN will zero the CHGTYPMAN bit */ reg_data = 0x1 << CDETCTRL1_CHGDETEN_SHIFT; max14577_update_reg(rmap, MAX14577_REG_CDETCTRL1, CDETCTRL1_CHGDETEN_MASK | CDETCTRL1_CHGTYPMAN_MASK, reg_data); /* * Wall-Adapter Rapid Charge, default on * Battery-Charger, default on */ reg_data = 0x1 << CHGCTRL2_VCHGR_RC_SHIFT; reg_data |= 0x1 << CHGCTRL2_MBCHOSTEN_SHIFT; max14577_write_reg(rmap, MAX14577_REG_CHGCTRL2, reg_data); /* Auto Charging Stop, default off */ reg_data = 0x0 << CHGCTRL6_AUTOSTOP_SHIFT; max14577_write_reg(rmap, MAX14577_REG_CHGCTRL6, reg_data); ret = max14577_init_constant_voltage(chg, chg->pdata->constant_uvolt); if (ret) return ret; ret = max14577_init_eoc(chg, chg->pdata->eoc_uamp); if (ret) return ret; ret = max14577_init_fast_charge(chg, chg->pdata->fast_charge_uamp); if (ret) return ret; ret = max14577_set_fast_charge_timer(chg, MAXIM_CHARGER_FAST_CHARGE_TIMER_DEFAULT); if (ret) return ret; /* Initialize Overvoltage-Protection Threshold */ switch (chg->pdata->ovp_uvolt) { case 7500000: reg_data = 0x0; break; case 6000000: case 6500000: case 7000000: reg_data = 0x1 + (chg->pdata->ovp_uvolt - 6000000) / 500000; break; default: dev_err(chg->dev, "Wrong value for OVP: %u\n", chg->pdata->ovp_uvolt); return -EINVAL; } reg_data <<= CHGCTRL7_OTPCGHCVS_SHIFT; max14577_write_reg(rmap, MAX14577_REG_CHGCTRL7, reg_data); return 0; } /* Support property from charger */ static enum power_supply_property max14577_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_MODEL_NAME, POWER_SUPPLY_PROP_MANUFACTURER, }; static const char * const model_names[] = { [MAXIM_DEVICE_TYPE_UNKNOWN] = "MAX14577-like", [MAXIM_DEVICE_TYPE_MAX14577] = "MAX14577", [MAXIM_DEVICE_TYPE_MAX77836] = "MAX77836", }; static const char *manufacturer = "Maxim Integrated"; static int max14577_charger_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) { struct max14577_charger *chg = power_supply_get_drvdata(psy); int ret = 0; switch (psp) { case POWER_SUPPLY_PROP_STATUS: ret = max14577_get_charger_state(chg, &val->intval); break; case POWER_SUPPLY_PROP_CHARGE_TYPE: ret = max14577_get_charge_type(chg, &val->intval); break; case POWER_SUPPLY_PROP_HEALTH: ret = max14577_get_battery_health(chg, &val->intval); break; case POWER_SUPPLY_PROP_PRESENT: ret = max14577_get_present(chg, &val->intval); break; case POWER_SUPPLY_PROP_ONLINE: ret = max14577_get_online(chg, &val->intval); break; case POWER_SUPPLY_PROP_MODEL_NAME: BUILD_BUG_ON(ARRAY_SIZE(model_names) != MAXIM_DEVICE_TYPE_NUM); val->strval = model_names[chg->max14577->dev_type]; break; case POWER_SUPPLY_PROP_MANUFACTURER: val->strval = manufacturer; break; default: return -EINVAL; } return ret; } static const struct power_supply_desc max14577_charger_desc = { .name = "max14577-charger", .type = POWER_SUPPLY_TYPE_BATTERY, .properties = max14577_charger_props, .num_properties = ARRAY_SIZE(max14577_charger_props), .get_property = max14577_charger_get_property, }; #ifdef CONFIG_OF static struct max14577_charger_platform_data *max14577_charger_dt_init( struct platform_device *pdev) { struct max14577_charger_platform_data *pdata; struct device_node *np = pdev->dev.of_node; int ret; if (!np) { dev_err(&pdev->dev, "No charger OF node\n"); return ERR_PTR(-EINVAL); } pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return ERR_PTR(-ENOMEM); ret = of_property_read_u32(np, "maxim,constant-uvolt", &pdata->constant_uvolt); if (ret) { dev_err(&pdev->dev, "Cannot parse maxim,constant-uvolt field from DT\n"); return ERR_PTR(ret); } ret = of_property_read_u32(np, "maxim,fast-charge-uamp", &pdata->fast_charge_uamp); if (ret) { dev_err(&pdev->dev, "Cannot parse maxim,fast-charge-uamp field from DT\n"); return ERR_PTR(ret); } ret = of_property_read_u32(np, "maxim,eoc-uamp", &pdata->eoc_uamp); if (ret) { dev_err(&pdev->dev, "Cannot parse maxim,eoc-uamp field from DT\n"); return ERR_PTR(ret); } ret = of_property_read_u32(np, "maxim,ovp-uvolt", &pdata->ovp_uvolt); if (ret) { dev_err(&pdev->dev, "Cannot parse maxim,ovp-uvolt field from DT\n"); return ERR_PTR(ret); } return pdata; } #else /* CONFIG_OF */ static struct max14577_charger_platform_data *max14577_charger_dt_init( struct platform_device *pdev) { return NULL; } #endif /* CONFIG_OF */ static ssize_t show_fast_charge_timer(struct device *dev, struct device_attribute *attr, char *buf) { struct max14577_charger *chg = dev_get_drvdata(dev); u8 reg_data; int ret; unsigned int val; ret = max14577_read_reg(chg->max14577->regmap, MAX14577_REG_CHGCTRL1, ®_data); if (ret) return ret; reg_data &= CHGCTRL1_TCHW_MASK; reg_data >>= CHGCTRL1_TCHW_SHIFT; switch (reg_data) { case 0x2 ... 0x4: val = reg_data + 3; break; case 0x7: val = 0; break; default: val = 5; break; } return scnprintf(buf, PAGE_SIZE, "%u\n", val); } static ssize_t store_fast_charge_timer(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct max14577_charger *chg = dev_get_drvdata(dev); unsigned long val; int ret; ret = kstrtoul(buf, 10, &val); if (ret) return ret; ret = max14577_set_fast_charge_timer(chg, val); if (ret) return ret; return count; } static DEVICE_ATTR(fast_charge_timer, S_IRUGO | S_IWUSR, show_fast_charge_timer, store_fast_charge_timer); static int max14577_charger_probe(struct platform_device *pdev) { struct max14577_charger *chg; struct power_supply_config psy_cfg = {}; struct max14577 *max14577 = 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->max14577 = max14577; chg->pdata = max14577_charger_dt_init(pdev); if (IS_ERR_OR_NULL(chg->pdata)) return PTR_ERR(chg->pdata); ret = max14577_charger_reg_init(chg); if (ret) return ret; ret = device_create_file(&pdev->dev, &dev_attr_fast_charge_timer); if (ret) { dev_err(&pdev->dev, "failed: create sysfs entry\n"); return ret; } psy_cfg.drv_data = chg; chg->charger = power_supply_register(&pdev->dev, &max14577_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; } /* Check for valid values for charger */ BUILD_BUG_ON(MAX14577_CHARGER_EOC_CURRENT_LIMIT_MIN + MAX14577_CHARGER_EOC_CURRENT_LIMIT_STEP * 0xf != MAX14577_CHARGER_EOC_CURRENT_LIMIT_MAX); return 0; err: device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer); return ret; } static int max14577_charger_remove(struct platform_device *pdev) { struct max14577_charger *chg = platform_get_drvdata(pdev); device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer); power_supply_unregister(chg->charger); return 0; } static const struct platform_device_id max14577_charger_id[] = { { "max14577-charger", MAXIM_DEVICE_TYPE_MAX14577, }, { "max77836-charger", MAXIM_DEVICE_TYPE_MAX77836, }, { } }; MODULE_DEVICE_TABLE(platform, max14577_charger_id); static struct platform_driver max14577_charger_driver = { .driver = { .name = "max14577-charger", }, .probe = max14577_charger_probe, .remove = max14577_charger_remove, .id_table = max14577_charger_id, }; module_platform_driver(max14577_charger_driver); MODULE_AUTHOR("Krzysztof Kozlowski <k.kozlowski@samsung.com>"); MODULE_DESCRIPTION("Maxim 14577/77836 charger driver"); MODULE_LICENSE("GPL");