/* * max17040_battery.c * fuel-gauge systems for lithium-ion (Li+) batteries * * Copyright (C) 2009 Samsung Electronics * Minkyu Kang * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #define MAX17040_VCELL_MSB 0x02 #define MAX17040_VCELL_LSB 0x03 #define MAX17040_SOC_MSB 0x04 #define MAX17040_SOC_LSB 0x05 #define MAX17040_MODE_MSB 0x06 #define MAX17040_MODE_LSB 0x07 #define MAX17040_VER_MSB 0x08 #define MAX17040_VER_LSB 0x09 #define MAX17040_RCOMP_MSB 0x0C #define MAX17040_RCOMP_LSB 0x0D #define MAX17040_CMD_MSB 0xFE #define MAX17040_CMD_LSB 0xFF #define MAX17040_DELAY msecs_to_jiffies(3000) #define MAX17040_BATTERY_FULL 99 #define POWER_OFF_VOLTAGE 3400000 #define POWER_MAX_VOLTAGE 4200000 //#define MAX17040_DEBUG 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 = container_of(psy, struct max17040_chip, battery); 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, u8 reg, u16 value) { struct i2c_msg msg; unsigned char buf[3]; int ret; buf[0] = reg; buf[1] = (value >> 8) & 0xFF; buf[2] = (value ) & 0xFF; msg.addr = client->addr; msg.flags = 0; msg.len = 3; msg.buf = (unsigned char *)&buf[0]; if((ret = i2c_transfer(client->adapter, &msg, 1)) < 0) { dev_err(&client->dev, "I2C write error: (%d) reg : 0x%02X value: 0x%04X\n", ret, reg, value); return ret; } return ret; } static int max17040_read_reg(struct i2c_client *client, u8 reg) { struct i2c_msg msg[2]; int ret; unsigned char temp[2]; msg[0].addr = client->addr; msg[0].flags = 0; msg[0].len = 1; msg[0].buf = (unsigned char *)® msg[1].addr = client->addr; msg[1].flags = I2C_M_RD; msg[1].len = 2; msg[1].buf = (unsigned char *)&temp[0]; if ((ret = i2c_transfer(client->adapter, msg, 2)) != 2) { dev_err(&client->dev, "I2C read error: (%d) reg: 0x%02X\n", ret, reg); return -EIO; } ret = ((temp[0] << 8) & 0xFF00) | (temp[1] & 0xFF); return ret; } static void max17040_reset(struct i2c_client *client) { max17040_write_reg(client, MAX17040_CMD_MSB, 0x5400); } static void max17040_get_vcell(struct i2c_client *client) { struct max17040_chip *chip = i2c_get_clientdata(client); chip->vcell = (max17040_read_reg(client, MAX17040_VCELL_MSB) >> 4) & 0xFFF; chip->vcell = (chip->vcell * 1250); #if defined(MAX17040_DEBUG) printk("chip->vcell = %d\n", chip->vcell); #endif } static void max17040_get_soc(struct i2c_client *client) { struct max17040_chip *chip = i2c_get_clientdata(client); chip->soc = (max17040_read_reg(client, MAX17040_SOC_MSB) >> 8) & 0xFF; chip->soc = (chip->soc - 2) * 100 / (100 - 2); if(chip->soc > 100) chip->soc = 100; if(chip->soc < 0 ) chip->soc = 0; if(chip->soc) { if(chip->vcell < POWER_OFF_VOLTAGE) chip->soc = 0; if(chip->soc > MAX17040_BATTERY_FULL) { if(chip->vcell < POWER_MAX_VOLTAGE) chip->soc = MAX17040_BATTERY_FULL; else chip->soc = MAX17040_BATTERY_FULL + 1; } } else { if(chip->vcell >= POWER_OFF_VOLTAGE) chip->soc = 1; } #if defined(MAX17040_DEBUG) printk("chip->soc = %d\n", chip->soc); #endif } static void max17040_get_version(struct i2c_client *client) { int ver; ver = max17040_read_reg(client, MAX17040_VER_MSB); dev_info(&client->dev, "MAX17040 Fuel-Gauge Ver %04X\n", ver); // Hardkerenl Odroid-A4 RCOMP #if defined(CONFIG_BOARD_ODROID_A4) max17040_write_reg(client, MAX17040_RCOMP_MSB, 0xD000); dev_info(&client->dev, "MAX17040 RCOMP Value %04X\n", max17040_read_reg(client, MAX17040_RCOMP_MSB)); #endif } static void max17040_get_online(struct i2c_client *client) { struct max17040_chip *chip = i2c_get_clientdata(client); chip->online = 1; if(chip->pdata) { if (chip->pdata->battery_online) chip->online = chip->pdata->battery_online(); } } static void max17040_get_status(struct i2c_client *client) { struct max17040_chip *chip = i2c_get_clientdata(client); if (chip->soc > MAX17040_BATTERY_FULL) chip->status = POWER_SUPPLY_STATUS_FULL; if (chip->pdata) { if (!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 { if(chip->status != POWER_SUPPLY_STATUS_DISCHARGING) chip->status = POWER_SUPPLY_STATUS_DISCHARGING; } } else { chip->status = POWER_SUPPLY_STATUS_DISCHARGING; } } static void max17040_work(struct work_struct *work) { struct max17040_chip *chip = container_of(work, struct max17040_chip, work.work); int old_vcell = chip->vcell, old_soc = chip->soc; max17040_get_vcell(chip->client); max17040_get_soc(chip->client); max17040_get_online(chip->client); max17040_get_status(chip->client); if((old_vcell != chip->vcell) || (old_soc != chip->soc)) { power_supply_changed(&chip->battery); #if defined(MAX17040_DEBUG) printk("%s : power_supply_changed!\n", __func__); #endif } schedule_delayed_work(&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 int __devinit max17040_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); struct max17040_chip *chip; int ret; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) return -EIO; chip = kzalloc(sizeof(*chip), GFP_KERNEL); if (!chip) return -ENOMEM; chip->client = client; chip->pdata = client->dev.platform_data; i2c_set_clientdata(client, chip); chip->battery.name = "max17040-battery"; chip->battery.type = POWER_SUPPLY_TYPE_BATTERY; chip->battery.get_property = max17040_get_property; chip->battery.properties = max17040_battery_props; chip->battery.num_properties = ARRAY_SIZE(max17040_battery_props); ret = power_supply_register(&client->dev, &chip->battery); if (ret) { dev_err(&client->dev, "failed: power supply register\n"); kfree(chip); return ret; } else { dev_info(&client->dev, "power supply max17040-battery registerd.\n"); } // max17040_reset(client); max17040_get_version(client); INIT_DELAYED_WORK_DEFERRABLE(&chip->work, max17040_work); schedule_delayed_work(&chip->work, MAX17040_DELAY); return 0; } static int __devexit max17040_remove(struct i2c_client *client) { struct max17040_chip *chip = i2c_get_clientdata(client); power_supply_unregister(&chip->battery); cancel_delayed_work(&chip->work); kfree(chip); return 0; } #ifdef CONFIG_PM static int max17040_suspend(struct i2c_client *client, pm_message_t state) { struct max17040_chip *chip = i2c_get_clientdata(client); cancel_delayed_work(&chip->work); return 0; } static int max17040_resume(struct i2c_client *client) { struct max17040_chip *chip = i2c_get_clientdata(client); schedule_delayed_work(&chip->work, MAX17040_DELAY); return 0; } #else #define max17040_suspend NULL #define max17040_resume NULL #endif /* CONFIG_PM */ static const struct i2c_device_id max17040_id[] = { { "max17040", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, max17040_id); static struct i2c_driver max17040_i2c_driver = { .driver = { .name = "max17040", }, .probe = max17040_probe, .remove = __devexit_p(max17040_remove), .suspend = max17040_suspend, .resume = max17040_resume, .id_table = max17040_id, }; static int __init max17040_init(void) { return i2c_add_driver(&max17040_i2c_driver); } module_init(max17040_init); static void __exit max17040_exit(void) { i2c_del_driver(&max17040_i2c_driver); } module_exit(max17040_exit); MODULE_AUTHOR("Hardkernel Co,.Ltd"); MODULE_DESCRIPTION("MAX17040 Fuel Gauge"); MODULE_LICENSE("GPL");