| /* |
| * Fuel gauge driver for Maxim 17042 / 8966 / 8997 |
| * Note that Maxim 8966 and 8997 are mfd and this is its subdevice. |
| * |
| * Copyright (C) 2011 Samsung Electronics |
| * MyungJoo Ham <myungjoo.ham@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. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| * |
| * This driver is based on max17040_battery.c |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/slab.h> |
| #include <linux/i2c.h> |
| #include <linux/mod_devicetable.h> |
| #include <linux/power_supply.h> |
| #include <linux/power/max17042_battery.h> |
| |
| struct max17042_chip { |
| struct i2c_client *client; |
| struct power_supply battery; |
| struct max17042_platform_data *pdata; |
| }; |
| |
| static int max17042_write_reg(struct i2c_client *client, u8 reg, u16 value) |
| { |
| int ret = i2c_smbus_write_word_data(client, reg, value); |
| |
| if (ret < 0) |
| dev_err(&client->dev, "%s: err %d\n", __func__, ret); |
| |
| return ret; |
| } |
| |
| static int max17042_read_reg(struct i2c_client *client, u8 reg) |
| { |
| int ret = i2c_smbus_read_word_data(client, reg); |
| |
| if (ret < 0) |
| dev_err(&client->dev, "%s: err %d\n", __func__, ret); |
| |
| return ret; |
| } |
| |
| static void max17042_set_reg(struct i2c_client *client, |
| struct max17042_reg_data *data, int size) |
| { |
| int i; |
| |
| for (i = 0; i < size; i++) |
| max17042_write_reg(client, data[i].addr, data[i].data); |
| } |
| |
| static enum power_supply_property max17042_battery_props[] = { |
| POWER_SUPPLY_PROP_PRESENT, |
| POWER_SUPPLY_PROP_CYCLE_COUNT, |
| POWER_SUPPLY_PROP_VOLTAGE_MAX, |
| POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN, |
| POWER_SUPPLY_PROP_VOLTAGE_NOW, |
| POWER_SUPPLY_PROP_VOLTAGE_AVG, |
| POWER_SUPPLY_PROP_CAPACITY, |
| POWER_SUPPLY_PROP_CHARGE_FULL, |
| POWER_SUPPLY_PROP_TEMP, |
| POWER_SUPPLY_PROP_CURRENT_NOW, |
| POWER_SUPPLY_PROP_CURRENT_AVG, |
| }; |
| |
| static int max17042_get_property(struct power_supply *psy, |
| enum power_supply_property psp, |
| union power_supply_propval *val) |
| { |
| struct max17042_chip *chip = container_of(psy, |
| struct max17042_chip, battery); |
| |
| switch (psp) { |
| case POWER_SUPPLY_PROP_PRESENT: |
| val->intval = max17042_read_reg(chip->client, |
| MAX17042_STATUS); |
| if (val->intval & MAX17042_STATUS_BattAbsent) |
| val->intval = 0; |
| else |
| val->intval = 1; |
| break; |
| case POWER_SUPPLY_PROP_CYCLE_COUNT: |
| val->intval = max17042_read_reg(chip->client, |
| MAX17042_Cycles); |
| break; |
| case POWER_SUPPLY_PROP_VOLTAGE_MAX: |
| val->intval = max17042_read_reg(chip->client, |
| MAX17042_MinMaxVolt); |
| val->intval >>= 8; |
| val->intval *= 20000; /* Units of LSB = 20mV */ |
| break; |
| case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN: |
| val->intval = max17042_read_reg(chip->client, |
| MAX17042_V_empty); |
| val->intval >>= 7; |
| val->intval *= 10000; /* Units of LSB = 10mV */ |
| break; |
| case POWER_SUPPLY_PROP_VOLTAGE_NOW: |
| val->intval = max17042_read_reg(chip->client, MAX17042_VCELL) |
| * 625 / 8; |
| break; |
| case POWER_SUPPLY_PROP_VOLTAGE_AVG: |
| val->intval = max17042_read_reg(chip->client, MAX17042_AvgVCELL) |
| * 625 / 8; |
| break; |
| case POWER_SUPPLY_PROP_CAPACITY: |
| val->intval = max17042_read_reg(chip->client, |
| MAX17042_SOC) / 256; |
| break; |
| case POWER_SUPPLY_PROP_CHARGE_FULL: |
| val->intval = max17042_read_reg(chip->client, |
| MAX17042_RepSOC); |
| if ((val->intval / 256) >= MAX17042_BATTERY_FULL) |
| val->intval = 1; |
| else if (val->intval >= 0) |
| val->intval = 0; |
| break; |
| case POWER_SUPPLY_PROP_TEMP: |
| val->intval = max17042_read_reg(chip->client, |
| MAX17042_TEMP); |
| /* The value is signed. */ |
| if (val->intval & 0x8000) { |
| val->intval = (0x7fff & ~val->intval) + 1; |
| val->intval *= -1; |
| } |
| /* The value is converted into deci-centigrade scale */ |
| /* Units of LSB = 1 / 256 degree Celsius */ |
| val->intval = val->intval * 10 / 256; |
| break; |
| case POWER_SUPPLY_PROP_CURRENT_NOW: |
| if (chip->pdata->enable_current_sense) { |
| val->intval = max17042_read_reg(chip->client, |
| MAX17042_Current); |
| if (val->intval & 0x8000) { |
| /* Negative */ |
| val->intval = ~val->intval & 0x7fff; |
| val->intval++; |
| val->intval *= -1; |
| } |
| val->intval *= 1562500 / chip->pdata->r_sns; |
| } else { |
| return -EINVAL; |
| } |
| break; |
| case POWER_SUPPLY_PROP_CURRENT_AVG: |
| if (chip->pdata->enable_current_sense) { |
| val->intval = max17042_read_reg(chip->client, |
| MAX17042_AvgCurrent); |
| if (val->intval & 0x8000) { |
| /* Negative */ |
| val->intval = ~val->intval & 0x7fff; |
| val->intval++; |
| val->intval *= -1; |
| } |
| val->intval *= 1562500 / chip->pdata->r_sns; |
| } else { |
| return -EINVAL; |
| } |
| break; |
| default: |
| return -EINVAL; |
| } |
| return 0; |
| } |
| |
| static int __devinit max17042_probe(struct i2c_client *client, |
| const struct i2c_device_id *id) |
| { |
| struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); |
| struct max17042_chip *chip; |
| int ret; |
| |
| if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) |
| 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 = "max17042_battery"; |
| chip->battery.type = POWER_SUPPLY_TYPE_BATTERY; |
| chip->battery.get_property = max17042_get_property; |
| chip->battery.properties = max17042_battery_props; |
| chip->battery.num_properties = ARRAY_SIZE(max17042_battery_props); |
| |
| /* When current is not measured, |
| * CURRENT_NOW and CURRENT_AVG properties should be invisible. */ |
| if (!chip->pdata->enable_current_sense) |
| chip->battery.num_properties -= 2; |
| |
| if (chip->pdata->r_sns == 0) |
| chip->pdata->r_sns = MAX17042_DEFAULT_SNS_RESISTOR; |
| |
| ret = power_supply_register(&client->dev, &chip->battery); |
| if (ret) { |
| dev_err(&client->dev, "failed: power supply register\n"); |
| kfree(chip); |
| return ret; |
| } |
| |
| /* Initialize registers according to values from the platform data */ |
| if (chip->pdata->init_data) |
| max17042_set_reg(client, chip->pdata->init_data, |
| chip->pdata->num_init_data); |
| |
| if (!chip->pdata->enable_current_sense) { |
| max17042_write_reg(client, MAX17042_CGAIN, 0x0000); |
| max17042_write_reg(client, MAX17042_MiscCFG, 0x0003); |
| max17042_write_reg(client, MAX17042_LearnCFG, 0x0007); |
| } |
| |
| return 0; |
| } |
| |
| static int __devexit max17042_remove(struct i2c_client *client) |
| { |
| struct max17042_chip *chip = i2c_get_clientdata(client); |
| |
| power_supply_unregister(&chip->battery); |
| kfree(chip); |
| return 0; |
| } |
| |
| static const struct i2c_device_id max17042_id[] = { |
| { "max17042", 0 }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, max17042_id); |
| |
| static struct i2c_driver max17042_i2c_driver = { |
| .driver = { |
| .name = "max17042", |
| }, |
| .probe = max17042_probe, |
| .remove = __devexit_p(max17042_remove), |
| .id_table = max17042_id, |
| }; |
| |
| static int __init max17042_init(void) |
| { |
| return i2c_add_driver(&max17042_i2c_driver); |
| } |
| module_init(max17042_init); |
| |
| static void __exit max17042_exit(void) |
| { |
| i2c_del_driver(&max17042_i2c_driver); |
| } |
| module_exit(max17042_exit); |
| |
| MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>"); |
| MODULE_DESCRIPTION("MAX17042 Fuel Gauge"); |
| MODULE_LICENSE("GPL"); |