+/*
+ * 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");