// SPDX-License-Identifier: GPL-2.0 // // max17040_battery.c // fuel-gauge systems for lithium-ion (Li+) batteries // // Copyright (C) 2009 Samsung Electronics // Minkyu Kang <mk7.kang@samsung.com> #include <linux/module.h> #include <linux/init.h> #include <linux/platform_device.h> #include <linux/mutex.h> #include <linux/err.h> #include <linux/i2c.h> #include <linux/delay.h> #include <linux/power_supply.h> #include <linux/max17040_battery.h> #include <linux/slab.h> #define MAX17040_VCELL 0x02 #define MAX17040_SOC 0x04 #define MAX17040_MODE 0x06 #define MAX17040_VER 0x08 #define MAX17040_RCOMP 0x0C #define MAX17040_CMD 0xFE #define MAX17040_DELAY 1000 #define MAX17040_BATTERY_FULL 95 struct max17040_chip { struct i2c_client *client; struct delayed_work work; struct power_supply *battery; struct max17040_platform_data *pdata; /* State Of Connect */ int online; /* battery voltage */ int vcell; /* battery capacity */ int soc; /* State Of Charge */ int status; }; static int max17040_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) { struct max17040_chip *chip = power_supply_get_drvdata(psy); switch (psp) { case POWER_SUPPLY_PROP_STATUS: val->intval = chip->status; break; case POWER_SUPPLY_PROP_ONLINE: val->intval = chip->online; break; case POWER_SUPPLY_PROP_VOLTAGE_NOW: val->intval = chip->vcell; break; case POWER_SUPPLY_PROP_CAPACITY: val->intval = chip->soc; break; default: return -EINVAL; } return 0; } static int max17040_write_reg(struct i2c_client *client, int reg, u16 value) { int ret; ret = i2c_smbus_write_word_swapped(client, reg, value); if (ret < 0) dev_err(&client->dev, "%s: err %d\n", __func__, ret); return ret; } static int max17040_read_reg(struct i2c_client *client, int reg) { int ret; ret = i2c_smbus_read_word_swapped(client, reg); if (ret < 0) dev_err(&client->dev, "%s: err %d\n", __func__, ret); return ret; } static void max17040_reset(struct i2c_client *client) { max17040_write_reg(client, MAX17040_CMD, 0x0054); } static void max17040_get_vcell(struct i2c_client *client) { struct max17040_chip *chip = i2c_get_clientdata(client); u16 vcell; vcell = max17040_read_reg(client, MAX17040_VCELL); chip->vcell = vcell; } static void max17040_get_soc(struct i2c_client *client) { struct max17040_chip *chip = i2c_get_clientdata(client); u16 soc; soc = max17040_read_reg(client, MAX17040_SOC); chip->soc = (soc >> 8); } static void max17040_get_version(struct i2c_client *client) { u16 version; version = max17040_read_reg(client, MAX17040_VER); dev_info(&client->dev, "MAX17040 Fuel-Gauge Ver 0x%x\n", version); } static void max17040_get_online(struct i2c_client *client) { struct max17040_chip *chip = i2c_get_clientdata(client); if (chip->pdata && chip->pdata->battery_online) chip->online = chip->pdata->battery_online(); else chip->online = 1; } static void max17040_get_status(struct i2c_client *client) { struct max17040_chip *chip = i2c_get_clientdata(client); if (!chip->pdata || !chip->pdata->charger_online || !chip->pdata->charger_enable) { chip->status = POWER_SUPPLY_STATUS_UNKNOWN; return; } if (chip->pdata->charger_online()) { if (chip->pdata->charger_enable()) chip->status = POWER_SUPPLY_STATUS_CHARGING; else chip->status = POWER_SUPPLY_STATUS_NOT_CHARGING; } else { chip->status = POWER_SUPPLY_STATUS_DISCHARGING; } if (chip->soc > MAX17040_BATTERY_FULL) chip->status = POWER_SUPPLY_STATUS_FULL; } static void max17040_work(struct work_struct *work) { struct max17040_chip *chip; chip = container_of(work, struct max17040_chip, work.work); max17040_get_vcell(chip->client); max17040_get_soc(chip->client); max17040_get_online(chip->client); max17040_get_status(chip->client); queue_delayed_work(system_power_efficient_wq, &chip->work, MAX17040_DELAY); } static enum power_supply_property max17040_battery_props[] = { POWER_SUPPLY_PROP_STATUS, POWER_SUPPLY_PROP_ONLINE, POWER_SUPPLY_PROP_VOLTAGE_NOW, POWER_SUPPLY_PROP_CAPACITY, }; static const struct power_supply_desc max17040_battery_desc = { .name = "battery", .type = POWER_SUPPLY_TYPE_BATTERY, .get_property = max17040_get_property, .properties = max17040_battery_props, .num_properties = ARRAY_SIZE(max17040_battery_props), }; static int max17040_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct i2c_adapter *adapter = client->adapter; struct power_supply_config psy_cfg = {}; struct max17040_chip *chip; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) return -EIO; chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); if (!chip) return -ENOMEM; chip->client = client; chip->pdata = client->dev.platform_data; i2c_set_clientdata(client, chip); psy_cfg.drv_data = chip; chip->battery = power_supply_register(&client->dev, &max17040_battery_desc, &psy_cfg); if (IS_ERR(chip->battery)) { dev_err(&client->dev, "failed: power supply register\n"); return PTR_ERR(chip->battery); } max17040_reset(client); max17040_get_version(client); INIT_DEFERRABLE_WORK(&chip->work, max17040_work); queue_delayed_work(system_power_efficient_wq, &chip->work, MAX17040_DELAY); return 0; } static int max17040_remove(struct i2c_client *client) { struct max17040_chip *chip = i2c_get_clientdata(client); power_supply_unregister(chip->battery); cancel_delayed_work(&chip->work); return 0; } #ifdef CONFIG_PM_SLEEP static int max17040_suspend(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct max17040_chip *chip = i2c_get_clientdata(client); cancel_delayed_work(&chip->work); return 0; } static int max17040_resume(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct max17040_chip *chip = i2c_get_clientdata(client); queue_delayed_work(system_power_efficient_wq, &chip->work, MAX17040_DELAY); return 0; } static SIMPLE_DEV_PM_OPS(max17040_pm_ops, max17040_suspend, max17040_resume); #define MAX17040_PM_OPS (&max17040_pm_ops) #else #define MAX17040_PM_OPS NULL #endif /* CONFIG_PM_SLEEP */ static const struct i2c_device_id max17040_id[] = { { "max17040" }, { "max77836-battery" }, { } }; MODULE_DEVICE_TABLE(i2c, max17040_id); static const struct of_device_id max17040_of_match[] = { { .compatible = "maxim,max17040" }, { .compatible = "maxim,max77836-battery" }, { }, }; MODULE_DEVICE_TABLE(of, max17040_of_match); static struct i2c_driver max17040_i2c_driver = { .driver = { .name = "max17040", .of_match_table = max17040_of_match, .pm = MAX17040_PM_OPS, }, .probe = max17040_probe, .remove = max17040_remove, .id_table = max17040_id, }; module_i2c_driver(max17040_i2c_driver); MODULE_AUTHOR("Minkyu Kang <mk7.kang@samsung.com>"); MODULE_DESCRIPTION("MAX17040 Fuel Gauge"); MODULE_LICENSE("GPL");