diff options
Diffstat (limited to 'drivers/power/max14577_charger.c')
| -rw-r--r-- | drivers/power/max14577_charger.c | 311 |
1 files changed, 311 insertions, 0 deletions
diff --git a/drivers/power/max14577_charger.c b/drivers/power/max14577_charger.c new file mode 100644 index 00000000000..fad2a75b360 --- /dev/null +++ b/drivers/power/max14577_charger.c @@ -0,0 +1,311 @@ +/* + * Battery charger driver for the Maxim 14577 + * + * Copyright (C) 2013 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> + +struct max14577_charger { + struct device *dev; + struct max14577 *max14577; + struct power_supply charger; + + unsigned int charging_state; + unsigned int battery_state; +}; + +static int max14577_get_charger_state(struct max14577_charger *chg) +{ + struct regmap *rmap = chg->max14577->regmap; + int state = POWER_SUPPLY_STATUS_DISCHARGING; + 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/ + */ + max14577_read_reg(rmap, MAX14577_CHG_REG_CHG_CTRL2, ®_data); + if ((reg_data & CHGCTRL2_MBCHOSTEN_MASK) == 0) + goto state_set; + + max14577_read_reg(rmap, MAX14577_CHG_REG_STATUS3, ®_data); + if (reg_data & STATUS3_CGMBC_MASK) { + /* Charger or USB-cable is connected */ + if (reg_data & STATUS3_EOC_MASK) + state = POWER_SUPPLY_STATUS_FULL; + else + state = POWER_SUPPLY_STATUS_CHARGING; + goto state_set; + } + +state_set: + chg->charging_state = state; + return state; +} + +/* + * Supported charge types: + * - POWER_SUPPLY_CHARGE_TYPE_NONE + * - POWER_SUPPLY_CHARGE_TYPE_FAST + */ +static int max14577_get_charge_type(struct max14577_charger *chg) +{ + /* + * 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." + */ + if (max14577_get_charger_state(chg) == POWER_SUPPLY_STATUS_CHARGING) + return POWER_SUPPLY_CHARGE_TYPE_FAST; + return POWER_SUPPLY_CHARGE_TYPE_NONE; +} + +static int max14577_get_online(struct max14577_charger *chg) +{ + struct regmap *rmap = chg->max14577->regmap; + u8 reg_data; + + max14577_read_reg(rmap, MAX14577_MUIC_REG_STATUS2, ®_data); + reg_data = ((reg_data & STATUS2_CHGTYP_MASK) >> STATUS2_CHGTYP_SHIFT); + switch (reg_data) { + 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: + return 1; + case MAX14577_CHARGER_TYPE_NONE: + case MAX14577_CHARGER_TYPE_DOWNSTREAM_PORT: + case MAX14577_CHARGER_TYPE_RESERVED: + default: + 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) +{ + struct regmap *rmap = chg->max14577->regmap; + int state = POWER_SUPPLY_HEALTH_GOOD; + u8 reg_data; + + max14577_read_reg(rmap, MAX14577_MUIC_REG_STATUS2, ®_data); + reg_data = ((reg_data & STATUS2_CHGTYP_MASK) >> STATUS2_CHGTYP_SHIFT); + if (reg_data == MAX14577_CHARGER_TYPE_DEAD_BATTERY) { + state = POWER_SUPPLY_HEALTH_DEAD; + goto state_set; + } + + max14577_read_reg(rmap, MAX14577_CHG_REG_STATUS3, ®_data); + if (reg_data & STATUS3_OVP_MASK) { + state = POWER_SUPPLY_HEALTH_OVERVOLTAGE; + goto state_set; + } + +state_set: + chg->battery_state = state; + return state; +} + +/* + * 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) +{ + return 1; +} + +/* + * 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 void max14577_charger_reg_init(struct max14577_charger *chg) +{ + struct regmap *rmap = chg->max14577->regmap; + u8 reg_data; + + /* + * 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); + + /* Battery Fast-Charge Timer, from SM-V700: 6hrs */ + reg_data = 0x3 << CHGCTRL1_TCHW_SHIFT; + max14577_write_reg(rmap, MAX14577_REG_CHGCTRL1, 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); + + /* Battery-Charger Constant Voltage (CV) Mode, from SM-V700: 4.35V */ + reg_data = 0xf << CHGCTRL3_MBCCVWRC_SHIFT; + max14577_write_reg(rmap, MAX14577_REG_CHGCTRL3, reg_data); + + /* + * Fast Battery-Charge Current Low, default 200-950mA + * Fast Battery-Charge Current High, from SM-V700: 450mA + */ + reg_data = 0x1 << CHGCTRL4_MBCICHWRCL_SHIFT; + reg_data |= 0x5 << CHGCTRL4_MBCICHWRCH_SHIFT; + max14577_write_reg(rmap, MAX14577_REG_CHGCTRL4, reg_data); + + /* End-of-Charge Current, from SM-V700: 50mA */ + reg_data = 0x0 << CHGCTRL5_EOCS_SHIFT; + max14577_write_reg(rmap, MAX14577_REG_CHGCTRL5, reg_data); + + /* Auto Charging Stop, default off */ + reg_data = 0x0 << CHGCTRL6_AUTOSTOP_SHIFT; + max14577_write_reg(rmap, MAX14577_REG_CHGCTRL6, reg_data); + + /* Overvoltage-Protection Threshold, from SM-V700: 6.5V */ + reg_data = 0x2 << CHGCTRL7_OTPCGHCVS_SHIFT; + max14577_write_reg(rmap, MAX14577_REG_CHGCTRL7, reg_data); +} + +/* 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 *model_name = "MAX14577"; +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 = container_of(psy, + struct max14577_charger, + charger); + int ret = 0; + + switch (psp) { + case POWER_SUPPLY_PROP_STATUS: + val->intval = max14577_get_charger_state(chg); + break; + case POWER_SUPPLY_PROP_CHARGE_TYPE: + val->intval = max14577_get_charge_type(chg); + break; + case POWER_SUPPLY_PROP_HEALTH: + val->intval = max14577_get_battery_health(chg); + break; + case POWER_SUPPLY_PROP_PRESENT: + val->intval = max14577_get_present(chg); + break; + case POWER_SUPPLY_PROP_ONLINE: + val->intval = max14577_get_online(chg); + break; + case POWER_SUPPLY_PROP_MODEL_NAME: + val->strval = model_name; + break; + case POWER_SUPPLY_PROP_MANUFACTURER: + val->strval = manufacturer; + break; + default: + return -EINVAL; + } + + return ret; +} + +static int max14577_charger_probe(struct platform_device *pdev) +{ + struct max14577_charger *chg; + 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; + + max14577_charger_reg_init(chg); + + chg->charger.name = "max14577-charger", + chg->charger.type = POWER_SUPPLY_TYPE_BATTERY, + chg->charger.properties = max14577_charger_props, + chg->charger.num_properties = ARRAY_SIZE(max14577_charger_props), + chg->charger.get_property = max14577_charger_get_property, + + ret = power_supply_register(&pdev->dev, &chg->charger); + if (ret) { + dev_err(&pdev->dev, "failed: power supply register\n"); + return ret; + } + + return 0; +} + +static int max14577_charger_remove(struct platform_device *pdev) +{ + struct max14577_charger *chg = platform_get_drvdata(pdev); + + power_supply_unregister(&chg->charger); + + return 0; +} + +static struct platform_driver max14577_charger_driver = { + .driver = { + .owner = THIS_MODULE, + .name = "max14577-charger", + }, + .probe = max14577_charger_probe, + .remove = max14577_charger_remove, +}; +module_platform_driver(max14577_charger_driver); + +MODULE_AUTHOR("Krzysztof Kozlowski <k.kozlowski@samsung.com>"); +MODULE_DESCRIPTION("MAXIM 14577 charger driver"); +MODULE_LICENSE("GPL"); |